description: A lengthy guide to making simple, inclusive sites focused on content before form. Emphasizes brutalist design and accessibility to include under-represented users.
The following applies to minimal websites that focus primarily on text. It does not apply to websites that have a lot of non-textual content. It also does not apply to websites that focus more on generating revenue or pleasing investors than being inclusive.
<prole="doc-tip">If you find the article too long, just read the introduction and conclusion. The table of contents should help you skim.<prole="doc-tip">
I realize not everybody's going to ditch the Web and switch to Gemini or Gopher today (that'll take, like, a month at the longest). Until that happens, here's a non-exhaustive, highly-opinionated list of best practices for websites that focus primarily on text. I don't expect anybody to fully agree with the list; nonetheless, the article should have _some_ useful information for any web content author or front-end web developer.
My primary focus is [inclusive design](https://100daysofa11y.com/2019/12/03/accommodation-versus-inclusive-design/). Specifically, I focus on supporting _under­represented ways to read a page_. Not all users load a page in a common web-browser and navigate effortlessly with their eyes and hands. Authors often neglect people who read through accessibility tools, tiny viewports, machine translators, "reading mode" implemen­tations, the Tor network, printouts, hostile networks, and uncommon browsers, to name a few. I list more niches in [the conclusion](#conclusion). Compatibility with so many niches sounds far more daunting than it really is: if you only selectively override browser defaults and use plain-old, semantic HTML (<abbrtitle="plain-old, semantic HTML">POSH</abbr>), you've done half of the work already.
One of the core ideas behind the flavor of inclusive design I present is being _inclusive by default._ Web pages shouldn't use accessible overlays, reduced-data modes, or other personal­izations if these features can be available all the time. Of course, some features conflict; you can't display a light and dark color scheme simultaneously. Personal­ization is a fallback strategy to resolve conflicting needs. Dispro­portionately under­represented needs deserve dispro­portionately greater attention, so they come before personal preferences instead of being relegated to a separate lane.
Another focus is minimalism. [Progressive enhancement](https://en.wikipedia.org/wiki/Progressive_enhancement) is a simple, safe idea that tries to incorporate some responsibility into the design process without rocking the boat too much. I don't find it radical enough. In addition to progressive enhancement, I prefer limiting any enhancements to ones that have been demonstrated to solve specific accessibility, security, performance, or significant usability problems faced by people _besides me._
I'd like to re-iterate yet another time that this only applies to websites that primarily focus on text. If graphics, interactivity, etc. are an important part of your website, less of the article applies. My hope is for readers to consider a subset of this page the next time they build a website, and _address the trade-offs they make when they deviate._ I don't expect--or want--anybody to follow all of my advice, because doing so would make the Web quite a boring place!
I'll cite the Web Accessibility Initiative's (<abbrtitle="Web Accessibility Initiative">WAI</abbr>) <cite>[Techniques for WCAG 2.2](https://www.w3.org/WAI/WCAG22/Techniques/)</cite> a number of times. Unlike the <cite>Web Content Accessibility Guidelines</cite> (<abbrtitle="Web Content Accessibility Guidelines">WCAG</abbr>), the Techniques document does not list requirements; rather, it serves to non-exhaustively educate authors about _how_ to use specific technologies to comply with the WCAG. I don't find much utility in the technology-agnostic goals enumerated by the WCAG without the accompanying technology-specific techniques to meet those goals.
One of the defining differences between textual websites and advanced Web 2.0 sites/apps is safety. Most browser vulnera­bilities are related to modern Web features like JavaScript and WebGL. The simplicity of basic textual websites _should_ guarantee some extra safety; however, webmasters need to take additional measures to ensure limited use of "modern" risky features.
All of the simplicity in the world won't protect a page from unsafe content injection by an intermediary. Proper use of TLS protects against page alteration in transit and ensures a limited degree of privacy. Test your TLS setup with <atranslate="no"href="https://testssl.sh/">testssl.sh</a> and [Webbkoll](https://webbkoll.dataskydd.net/).
If your OpenSSL (or equivalent) version is outdated or you don't want to download and run a shell script, SSL Labs' [SSL Server Test](https://www.ssllabs.com/ssltest/) should be equivalent to testssl.sh. Mozilla's [HTTP Observatory](https://observatory.mozilla.org/) offers a subset of Webbkoll's features and is a bit out of date (and requires JavaScript), but it also gives a beginner-friendly score. Most sites should strive for at least a 50, but a score of 100 or even 120 shouldn't be too hard to reach.
A false sense of security is far worse than transparent insecurity. Don't offer broken TLS ciphers, including TLS 1.0 and 1.1. Vintage computers can run TLS 1.2 implemen­tations such as BearSSL surprisingly efficiently, leverage a TLS terminator, or they can use a plain unencrypted connection. A broken cipher suite is security theater.
Consider taking hardening measures to maximize the security benefits made possible by the simplicity of textual websites, starting with script removal.
JavaScript and WebAssembly are responsible for the bulk of modern web exploits. If that isn't reason enough, most [non-mainstream search indexes](./../../../2021/03/10/search-engines-with-own-indexes.html) have little to no support for JavaScript. Ideally, a text-oriented site can enforce a scripting ban at the [Content Security Policy](https://developer.mozilla.org/en-US/docs/Web/HTTP/CSP) (<abbrtitle="Content Security Policy">CSP</abbr>) level.
`default-src: 'none'` implies `script-src: 'none'`, causing a compliant browser to forbid the loading of scripts. Furthermore, the `sandbox` CSP directive forbids a [wide variety of risky actions](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/sandbox). While `script-src` restricts script loading, `sandbox` can also restrict script execution with stronger defenses against script injection (e.g. by a browser add-on).[^1] I added the `allow-same-origin` parameter so that these add-ons will still be able to function.[^2]
If you're able to control your HTTP headers, then use headers instead of a `<meta http=equiv>` tag. In addition to not supporting certain directives, a CSP in a `<meta>` tag might let some items slip through.
{{<quotation>}}
<blockquoteitemprop="text">
<p>
At the time of inserting the <code>meta</code> element to the document, it is
possible that some resources have already been fetched. For example, images might be stored in
the <ahref="https://html.spec.whatwg.org/multipage/images.html#list-of-available-images">list of available images</a> prior to dynamically inserting a <code>meta</code>
element with an <code>http-equiv</code> attribute in the Content security policy state.
Resources that have already been fetched are not guaranteed to be blocked by a Content
Please use progressive enhancement (<abbrtitle="progressive enhancement">PE</abbr>)[^3] throughout your site; every feature possible should be optional, and scripting is no exception.
I'm sure you're a great person, but your readers might not know that; don't expect them to trust your website. Your scripts should look as safe as possible to an untrusting eye. Avoid requesting permissions or using [sensitive APIs](https://browserleaks.com/javascript).
Finally, consider using your CSP to restrict script loading. If you must use inline scripts, selectively allow them with a hash or nonce. [Some recent CSP directives](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/trusted-types) restrict and enforce proper use of [trusted types](https://web.dev/trusted-types/).
Third-party content will complicate the CSP, allow more actors to track users, possibly slow page loading, and create more points of failure. Some privacy-conscious users actually block third-party content: while doing so is fingerprintable, it can reduce the amount of data collected about an already-identified user. Avoid third-party content, if at all possible.
Some web developers deliver resources using a third-party content delivery network (<abbrtitle="content delivery network">CDN</abbr>), such as jsDelivr or Unpkg. Traditional wisdom held that doing so would allow different websites to re-use cached resources; however, all mainstream browsers engines now [partition their caches](https://privacycg.github.io/storage-partitioning/) to prevent this behavior.
If you must use third-party content, use [subresource integrity](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity) (check the [<abbr title="Subresource Integrity">SRI</abbr> specification](https://www.w3.org/TR/SRI/)). This prevents alteration without your consent. If you wish to be extra careful, you could use SRI for first-party resources too.
Be sure to check the privacy policies for the third party services _and_ subscribe to updates, as their practices could impact the privacy of all your users.
For embedded third-party content (e.g. images), give extra consideration to the ["Beyond alt-text" section](#beyond-alt-text). Your page should be as useful as possible if the embedded content becomes inaccessible.
Nearly every Internet user has to deal with unreliable connections every now and then, even the most privileged. Developing regions lack modern Internet infrastructure; high-ranking executives travel frequently. Everybody hits the worst end of the bell-curve.
Reducing load time is especially useful to poorly-connected users. For much of the world, connectivity comes in short bursts during which loading time is precious. Chances of a connection failure or packet loss increase with time.
Optimal loading is a complex topic. Broadly, it covers three overlapping categories: reducing payload size, delivering content early, and reducing the number of requests and round trips.
HTML is a blocking resource: images and stylesheets will not load until the user agent loads and parses the HTML that calls them. To start loading above-the-fold images before the HTML parsing finishes, send a `link` HTTP header.
{{<codefigure>}} {{<codecaption>}} my website includes a `link` header to load an SVG that serves as my IndieWeb photo and favicon. Hash removed from filename for readability. {{</codecaption>}}
The browser cache is a valuable tool to save bandwidth and improve page speed, but it's not as reliable as many people seem to believe. Don't focus too much on "repeat view" performance.
Out of privacy concerns, most browsers no longer re-use cached content across sites; refer back to the [section on third-party content](#third-party-content) for more details. Privacy-conscious users (including all users using "private" or "incognito" sessions) will likely have their caches wiped between sessions.
Requesting a high number of cached resources can decrease performance of the cache, causing browsers to [bypass the cache](https://simonhearne.com/2020/network-faster-than-cache/). The effect is especially pronounced on low-end phones and mechanical hard drives.
One way to help browsers decide which disk-cached resources to prioritize is to use immutable assets. Include the `immutable` directive in your `cache-control` headers, and cache-bust modified assets by changing their URLs. You can also keep your asset counts low by combining textual assets (e.g. CSS) and inlining small resources.
{{<codefigure>}} {{<codecaption>}} The only external assets on my pages are images and a web app manifest (for icons); I mark these assets as "immutable" and cache-bust them by including checksums in their filenames. {{</codecaption>}}
In addition to HTML, CSS is also a blocking resource. You could pre-load your CSS using a `link` header. Alternatively: if your gzipped CSS is under **one kilobyte,** consider inlining it in the `<head>` using a `<style>` element. Simply inlining stylesheets can pose a security threat, but the `style-src`<abbrtitle="Content Security Policy">CSP</abbr> directive can mitigate this if you include a hash of your inline stylesheet sans trailing whitespace.
Consider inlining images under 250 bytes with a `data:` URI; that's the size at which cache-validation requests might outweigh the size of the image. My 32-pixel PNG site icon is under 150 bytes and inlines quite nicely. On this site's hidden service, it's often the only image on a page (the hidden service replaces SVGs with PNGs; see the section on [the Tor Browser](#the-tor-browser)). Inlining this image and the stylesheet allows my hidden service's homepage to load in a single request, which is a welcome improvement given the round-trip latency that plagues onion routing implemen­tations.
Download size matters, especially on metered connections. There's no shortage of advice concerning minimizing this easy-to-understand metric. Unfortunately, it alone doesn't give us the full picture: download size is not the exact same thing as time taken to deliver useful content to users.
Google's answer to this problem is "Core Web Vitals" containing metrics such as [the Speed Index](https://docs.webpagetest.org/metrics/speedindex/). These metrics aren't useless, but they are incredibly naive: they only take into account user-perceivable speed with an emphasis on user engagement, placing too little emphasis a page's actual resource use. Plenty of other factors exist.
Speed­Index is based on the idea that what counts is how fast the visible part of the website renders. It doesn't matter what's happening elsewhere on the page. It doesn't matter if the network is saturated and your phone is hot to the touch. It doesn't matter if the battery is visibly draining. Everything is OK as long as the part of the site in the viewport appears to pop into view right away.
Of course, it doesn’t matter how fast the site appears to load if the first thing the completed page does is serve an interstitial ad. Or, if like many mobile users, you start scrolling immediately and catch the 'unoptimized' part of the page with its pants down.
There is only one honest measure of web performance: **the time from when you click a link to when you've finished skipping the last ad.**
Understanding round-trips requires understanding your server's approach to congestion control.
Historically, TCP congestion control approaches typically set an initial window size to ten TCP packets and grew this value with each round-trip. Under most setups, this meant that the first round-trip could include 1460 bytes. The following round-trip could deliver under three kilobytes.[^4]
Nowadays, servers typically employ BBR-based congestion control. It allows for regular "spikes" in window size, but the initial window size is still small. Find more details in the slides from <spanclass="h-cite"itemprop="citation"itemscopeitemtype="https://schema.org/PresentationDigitalDocument"><citeclass="p-name"itemprop="name headline"><aclass="u-url"itemprop="url"href="https://labs.apnic.net/presentations/store/2019-09-05-bbr.pdf">TCP and BBR</a></cite> (<spanitemprop="encodingFormat">application/<wbr>pdf</span>) by {{<indieweb-personfirst-name="Geoff"last-name="Huston"itemprop="author"url="https://www.potaroo.net/"org="APNIC"org-url="https://www.apnic.net/">}} </span>
HTTP/3 uses QUIC instead of TCP, which makes things a bit different; the important thing to remember is that _user agents should be aware of all blocking resources **before** finishing the earliest possible round-trip._
Assume that your first impression must fit in the first kilobyte. Make good use of this golden kilobyte; most or all of it will likely be taken up by HTTP headers.[^5] Ideally, the first kilobyte transferred should inform the client of all blocking resources required, possibly using preload directives; all of these resources can then begin downloading over the same multiplexed HTTP/2 connection before the current round-trip finishes! Note that this works best if you took my earlier advice [to avoid third-party content](#third-party-content).
Apply these strategies in moderation. Including extra preload directives in your document markup might not help as much as you think, since their impact on page size could negate minor improvements. Micro-optimizations have diminishing returns; past a certain point, your effort is better spent elsewhere.
Loading content of unknown dimensions, such as images, can create layout shifts; the <abbrtitle="Web Incubator Community Group">WICG</abbr>'s <cite>[Layout Instability API](https://wicg.github.io/layout-instability/#sec-intro)</cite> describes the phenomenon in detail. Avoid layout shifts by including dimensions in HTML attributes. The simplest way to do so is by including unitless `width` and `height` values, but the `style` attribute could work too. I recommend staying away from the `style` attribute, or at least selectively allowing its use with the `style-src-attr` CSP directive.
Compression--especially static compression--dramatically reduces download sizes. My full-text RSS feed is about a quarter of a megabyte, but the Brotli-compressed version is about 70 kilobytes. Caddy supports this with a `precompressed` directive; Nginx requires the [ngx_brotli module](https://github.com/google/ngx_brotli) for Brotli compression.
When serving many resources at once (e.g., if a page has many images), HTTP/2 could offer a speed boost through multiplexing; use it if you can, but expect many clients to only support HTTP/1.1. HTTP/3 is unlikely to help textual websites much, so run a benchmark to see if it's worthwhile.
Consider caching static assets indefinitely with a year-long duration in their `cache-control` headers, possibly with an `immutable` parameter. If you have to update a static asset, cache-bust it by altering the URL. This approach should eliminate the need for an `etag` header on static assets.
Using [OCSP stapling](https://en.wikipedia.org/wiki/OCSP_stapling) eliminates the need to connect to a certificate authority, saving users a DNS lookup and allowing them to instead re-use a connection.
Consider the trade-offs involved in enabling 0-<abbrtitle="Round-Trip Time">RTT</abbr> for TLS 1.3. On one hand, it shaves off a round-trip during session resumption; on the other hand, it can enable replay attacks. 0-RTT shouldn't be too unsafe for idempotent GET requests of static content. For dynamic content, evaluate whether your backend is vulnerable to replay attacks described in [appendix E.5](https://www.rfc-editor.org/rfc/rfc8446.html#appendix-E.5) of the spec.
Many people use Tor out of necessity. On Tor, additional constraints apply.
For one, Tor users are encouraged to set the Tor Browser Bundle's (<abbrtitle="Tor Browser Bundle">TBB</abbr>) [security settings](https://tb-manual.torproject.org/en-US/security-settings/) to "safest". This disables scripts, MathML, some fonts, SVG images, and [other features](https://gitweb.torproject.org/torbutton.git/tree/modules/security-prefs.js). If your site has any SVG images, the Tor browser will download these just like Firefox would (to avoid fingerprinting) but will not render them.
Additionally, hopping between nodes in Tor circuits incurs latency, worsening the impacts of requiring multiple requests and round-trips. Try to minimise the number of requests to view a page.
If you use a CDN or some over­complicated website security stack, make sure it doesn't block Tor users or require them to enable JavaScript to complete a CAPTCHA. Tor Browser users are supposed to avoid fingerprinting vectors like JS and browser extensions, so requiring a JavaScript-<wbr>based CAPTCHA will effectively block many Tor users.
Tor users are unable to leverage media queries or client-hints to signal special needs. Pages need to be as accessible as possible _by default_. This should be a given, but it's doubly important when serving fingerprinting-averse readers.
### Hidden services
To go above and beyond, try mirroring your site to a Tor hidden service to reduce the need for exit nodes. Mirroring allows you to keep a separate version of your site optimized for the Tor browser.
Normally, optimizing specifically for a given user agent's quirks (especially in a separate version of a website) is a bad practice; however, the Tor Browser is a special case because there's no alternative available: Tor users should all use the same browser to avoid standing out. Sometimes, the Tor Browser pretends to have Firefox's capabilities: progressive enhancement and graceful degradation won't work when a browser lies about its functionality.
For example, my website's clearnet version uses some SVG images. Some browsers can't handle a given image format. The typical solution is to use a `<picture>` element containing `<source>` children of varying formats and a fallback `<img>` element using a legacy image format.
The Tor browser will download whichever format Firefox would, rather than whichever formats it actually supports. A `<picture>` element containing an SVG and a raster fallback won't help: the Tor browser will avoid fingerprinting by selecting the SVG format, not a fallback format. The image will not be rendered, so users will have downloaded the image only to see a white box.
I address the issue by not using any SVG images on [my hidden service](http://wgq3bd2kqoybhstp77i3wrzbfnsyd27wt34psaja4grqiezqircorkyd.onion/).
Lazy loading may or may not work. Some browsers, including Firefox and the Tor Browser, disable lazy-loading when the user turns off JavaScript. Turning it off makes sense because lazy-loading, like JavaScript, is a fingerprinting vector. Specifically, it identifies idiosyncratic scrolling patterns.
<p>Loading is only deferred when JavaScript is enabled. This is an anti-tracking measure, because if a user agent supported lazy loading when scripting is disabled, it would still be possible for a site to track a user's approximate scroll position throughout a session, by strategically placing images in a page's markup such that a server can track how many images are requested and when.</p>
The scope of this article is textual content supplemented by images. In that context, I don't think lazy loading is worthwhile because it often frustrates users on slow connections. I think I can speak for some of these users: mobile data near my home has a number of "dead zones" with abysmal download speeds, and my home's Wi-Fi repeater setup used to result in packet loss rates surpassing 60% (!!).
Users on poor connections have better things to do than idly wait for pages to load. They might open multiple links in background tabs to wait for them all to load at once, and/or switch to another task and come back when loading finishes. They might also open links while on a good connection before switching to a poor connection. For example, I often open several links on Wi-Fi before going out for a walk in a mobile-data dead-zone. A Reddit user reading an earlier version of this article described a [similar experience riding the train](https://i.reddit.com/r/web_design/comments/k0dmpj/an_opinionated_list_of_best_practices_for_textual/gdmxy4u/).
Unfortunately, pages with lazy loading don't finish loading off-screen images in the background. To load this content ahead of time, users need to switch to the loading page and slowly scroll to the end to ensure that all the important content appears on-screen and starts loading. Website owners shouldn't expect users to have to jump through these ridiculous hoops.
A common objection to my case against lazy-loading is that users may be more likely to click a link than scroll to the end, so pages should prioritize pre-loading the link. Pre-loading a page's essential resources is fine. Speculatively pre-loading content on separate pages isn't.
Many users with poor connections also have capped data, and would prefer that pages don't decide to predictively load many pages ahead-of-time for them. The overlap between these two groups grows especially pronounced as data cap overages trigger throttling; this is enough to trigger [a seasonal pattern in Japan](https://web.archive.org/web/20220402004738/https://nitter.pussthecat.org/yoavweiss/status/1195036487538003968).
Some go so far as to disable this behavior to avoid data overages. Savvy privacy-conscious users (including Tor Browser users) also generally disable speculative pre-loading since pre-loading behavior is fingerprintable.
Users who click a link _choose_ to load a full page. Loading pages that a user hasn't clicked on is making a choice for that user. I encourage adoption of "link" HTTP headers to pre-load essential and above-the-fold resources when possible, but doing so does not resolve the issues with lazy-loading: the people who are harmed by lazy loading are more likely to have pre-fetching disabled.
Moreover, determining the pages to prioritize for speculative pre-loading typically requires analytics and/or A/B testing. Enrolling users in a study (e.g. by collecting information about their behavior) without prior informed consent _in terms they fully understand_ demonstrates a disrespect for their autonomy. Furthermore: analytics typically represent all users equally, when developers should be giving disproportionate attention to marginalized users (e.g., disabled users). The convenience of the majority should not generally outweigh the needs of the minority. Many marginalized people don't wish to broadcast the fact that they have special needs, so don't rely on being able to figure out who's whom.
2. Yes, users could disable images. That's _their_ choice. If your page uses lazy loading, you've effectively (and probably unintention­ally) made that choice for a large number of users.
Nonetheless, expect some readers to have images disabled. Refer to [the "Beyond alt-text" section](#beyond-alt-text) to see how to best support this case.
Pages should finish making all `GET` network requests while loading. This makes it easy to load pages in the background before disconnecting. I singled out lazy-loading, but other factors can violate this constraint.
One example is pagination. It's easier to download one long article ahead of time, but inconvenient to load each page separately. Displaying content all at once also improves searchability. The single-page approach has obvious limits: don't expect users to happily download a single-page novel.
Another common offender is infinite-scrolling. In addition to requiring JavaScript, infinite-scrolling also makes it difficult for readers to find their old place upon re-visiting a page. This creates harsh consequences for accidental navigation. WordPress documentation lists [more problems with infinite scrolling](https://make.wordpress.org/accessibility/handbook/markup/infinite-scroll/)[^6].
A hybrid between the two is paginated content in which users click a "load next page" link to insert the next page at the end of the current page (typically using "dynamic content replacement"). It's essentially the same as infinite scrolling, except additional content is loaded after a click rather than by scrolling. This is only slightly less bad than infinite scrolling; it still has the same fundamental issue of allowing readers to lose their place.
I've discussed loading pages in the background, but what about saving a page offline (e.g. with <kbd>Ctrl</kbd> + <kbd>s</kbd>)? While lazy-loading won't interfere with the ability to save a complete page offline, some of these related issues can. Excessive pagination and inline scrolling make it impossible to download a complete page without manually scrolling or following pagination links to the end.
A similar image attribute that I _do_ recommend is the [`decoding` attribute](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/Img#attr-decoding). I typically use `decoding="async"` so that image decoding can be deferred.
<dfn>CSS containment</dfn> allows authors to isolate sub-trees of the DOM. Combined with a property like "content-visibility", it enables browsers to defer rendering of less essential below-the-fold content. Try to avoid the `hidden` parameter when `auto` is better:
`content-visibility: auto` is a more complex directive than `content-visibility: hidden`; rather than being similar to `display: none`, it adaptively hides/<wbr>displays an element's contents as they become <ahref="https://drafts.csswg.org/css-contain/#relevant-to-the-user">relevant to the user</a>. It also doesn’t hide its <ahref="https://drafts.csswg.org/css-contain/#skips-its-contents">skipped contents</a> from the user agent, so screen readers, in-page search, and other tools can still interact with it.
Leveraging containment is a progressive enhancement, so there aren't any serious implications for older browsers. I use it for my site footers and endnotes.
Using containment for content at the end of the page is relatively safe. Using it for content earlier in the page risks introducing [layout shifts](#layout-shifts). Eliminate the layout shifts by calculating a value for the `contain-intrinsic-size` property. <spanitemprop="mentions"itemscopeitemtype="https://schema.org/TechArticle">{{<cited-workurl="https://www.terluinwebdesign.nl/en/css/calculating-contain-intrinsic-size-for-content-visibility/"name="Calculating 'contain-intrinsic-size' for 'content-visibility'"extraName="headline">}}, by {{<indieweb-personfirst-name="Thijs"last-name="Terluin"url="https://www.terluinwebdesign.nl/en/about-us/thijs-terluin/"org="Teluin Webdesign"org-url="https://www.terluinwebdesign.nl/en/"itemprop="author">}}</span>, is a comprehensive guide to calculating intrinsic size values.
In-page search (e.g., using <kbd>Ctrl</kbd> + <kbd>f</kbd>) has been a basic feature in document readers well before browsers, and continues to be an essential feature today.
Searchability is a good reason to reason to prefer conveying information textually, when possible: video (especially without accurate captions), pictures of text, etc. aren't so easily searchable.
Web pages that hide content behind "show content" widgets are difficult to search through: users need to toggle "show content" for each item they wish to search. Often, in-page search highlights are hidden; [Reddit's atrocious redesign](#reddit-redesign) is a serious offender. If you need to hide some content for performance reasons, I described a less hostile way to do so in [the "other ways to defer content" section](#other-ways-to-defer-content).
Searching for the word "good" before and after a "see more" link is clicked. Both situations show a match, but only one of them allows us to view the match. Both screenshots are from the Reddit redesign.
Correct, consistent spelling is important to readers who use search. In-page search doesn't currently pick up misspelled words. If in-page search implemen­tations develop such a feature, some users may wish to sometimes turn it off; even Google Search implemented a "verbatim" mode for exact matches.
Moreover, some search implemen­tations (such as the one built into Firefox) support case-sensitive matching. Inconsistent capitalization of proper nouns, acronyms, and initialisms can make searching difficult.
Search is so essential to some users' ability to navigate that some desktop users enable "type-ahead" search, to automatically begin a search upon typing multiple characters.[^7] If you ignored my advice to avoid JavaScript, at least think twice before using it to define custom keyboard shortcuts which interfere with this type of functionality. I singled out type-ahead search, but there are countless other examples of uncommon keyboard behavior that JavaScript overrides interfere with.
Another problematic override is scroll-behavior. Enforcing smooth-scrolling (e.g., with the `scroll-behavior` CSS property) can interfere with the use of in-page search by slowing down jumps between matches. Rapidly darting around the page with smooth scrolling can cause motion sickness. Simply relying on users to override default behaviors violates the "inclusive by default" directive I encourage, since user preferences are fingerprintable and shift responsibility away from developers.
There's a complex solution to [turn off smooth scrolling for un-focused elements](https://schepp.dev/posts/smooth-scrolling-and-page-search/), but it doesn't address separate issues such as anchor-link navigation.
I recommend setting the default font to `sans-serif`. [`system-ui` causes issues](https://infinnie.github.io/blog/2017/systemui.html) among readers whose system fonts don't cover your website's charset.
If you really want, you could use serif instead of sans-serif; however, serif fonts tend to look worse on low-res monitors. Not every screen's <abbrtitle="Dots Per Inch">DPI</abbr> has three digits. Accommodate users' default zoom levels by keeping your font size the same as most similar websites.
To ship custom fonts is to assert that branding is more important than user choice. That might very well be a reasonable thing to do; branding isn't evil! That being said, textual websites in particular don't benefit much from branding. Beyond basic layout and optionally supporting dark mode, authors generally shouldn't dictate the presentation of their websites; that should be the job of the user agent. Most websites are not important enough to look completely different from the rest of the user's system.
A personal example: I set my preferred browser font to `sans-serif`, and map it to my preferred font in my computer's fontconfig settings. Now every website that uses sans-serif will have my preferred font. Sites with sans-serif blend into the users' systems instead of sticking out.
### But most users don't change their fonts...
The "users don't know better and need us to make decisions for them" mindset isn't without merits; however, in my opinion, it's overused. Using system fonts doesn't make your website harder to use, but it does make it smaller and stick out less to the subset of users who care enough about fonts to change them. This argument isn't about making software easier for non-technical users; it's about branding by asserting a personal preference.
It's not a good idea to require users to automatically override website stylesheets to see their preferred fonts. Doing so would break websites that use fonts such as Font Awesome to display vector icons. We shouldn't have these users constantly battle with websites the same way that many ad- and script-blocking users (myself included) already do when there's a better option.
That being said, many users _do_ actually override stylesheets. We shouldn't _require_ them to do so, but we should keep our pages from breaking in case they do. Pages following this article's advice will probably work perfectly well in these cases without any extra effort.
### Font finger­printing concerns
Some people raised fingerprinting concerns when I suggested using the default "sans-serif" font. Websites could see which font this maps to in order to identify users.
I don't know much about fingerprinting, except that you can't do font enumeration or accurately calculate font metrics without JavaScript. Since text-based websites that follow these best-practices don't send requests after the page loads and have no scripts, they shouldn't be able to fingerprint via font identification.
Other websites can still fingerprint via font enumeration using JavaScript. They don't need to stop at seeing what sans-serif maps to: they can see available fonts on a user's system,[^8] the user's canvas fingerprint, window dimensions, etc. Some of these can be mitigated by [Firefox's protections against fingerprinting](https://support.mozilla.org/en-US/kb/firefox-protection-against-fingerprinting), but these protections understandably override user font preferences.
Ultimately, surveillance self-defense on the web is an arms race full of trade-offs. If you want both privacy and customizability, the web is not the place to look; try Gemini or Gopher instead.
### Zoom and font size
Browsers allow users to zoom by adjusting size metrics. Additionally, most browsers allow users to specify a minimum font size. Minimum sizes don't always work; setting size values in `px` can override these settings.
In your stylesheets, avoid using `px` where possible. Define sizes and dimensions using relative units (preferably `em`). Exceptions exist for some decorations[^9] (e.g. borders), but they are uncommon.
* Don't include significant information that isn't present in the image; I'll cover how to handle supple­mentary information in the next subsections.
The <abbrtitle="Web Accessibility Initiative">WAI</abbr> provides some guidelines in <cite>[An `alt` Decision Tree](https://www.w3.org/WAI/tutorials/images/decision-tree/)</cite>. It's a little lacking in nuance, but makes for a good starting point. Remember that guidelines and "good practices" always have exceptions.
Alt text isn't just for blind readers; sighted readers who can't load an image will see alt-text in its place. This alt text might be confined to the image container, so small images should have shorter alt text.
Alt text should be limited to describing content of the image. It lacks context. To make things worse, images can contain a great deal of information. Sighted people can "filter" this information and find areas to focus on; alt text should capture this detail. However, sighted users' understanding of this detail can be informed by surrounding less-essential detail.
Blind users might struggle to view images in context; they can't easily scan the text before and after an image non-linearly if there's no semantic connection between them. Charles McCathieNevile described this experience by comparing screen reading to [reading through a drinking straw](#straw-analogy).
Being sighted and loading images can introduce issues of its own. Sometimes, sighted readers might focus on the _wrong_ part of an image. How can you give readers the missing context and tell them what to focus on?
2. After the image, describe your interpretation of important details.
This is somewhat similar to the way most students in primary and secondary schools are taught to cite evidence in essays. On that note: remember that these are weak norms, not rules. Deviate where appropriate, just as students should as they learn to write.
### Figures
A <dfn>figure</dfn> is any sort of self-contained information that is referenced by--but somewhat distinct from--body content. Items that make for good figures are often found in [floating blocks](https://en.wikipedia.org/wiki/Page_layout#Floating_block) of print material.
Consider using a `<figure>` element when employing the previous section's two-part strategy. Place one of the two aforementioned pieces of information in a `<figcaption>`; the caption can come before or after the image.
Figures aren't just for images; they're for any self-contained referenced content that's closer to the surrounding body than an `<aside>`. Some example items that could use a caption:
Figures and captions have loose guidelines, and nearly everything I said on the matter is full of exceptions. A figure need not have a caption, but the majority benefit from one. It need not contain a single main element, but most probably should.
I personally try to maintain the flow of an article even if its figures and captions are completely removed or moved to an appendix. A figure is a "self-contained" block: user agents may re-position figure captions relative to the main figure content, or move the entire figure elsewhere; this is especially common in [reading-mode implemen­tations](#non-browsers-reading-mode). The HTML specification explicitly notes this behavior.
<p>When a <code>figure</code> is referred to from the main content of the document by identifying
it by its caption (e.g., by figure number), it enables such content to be easily moved away from
that primary content, e.g., to the side of the page, to dedicated pages, or to an appendix,
without affecting the flow of the document.</p>
<p>If a <code>figure</code> element is <ahref="https://html.spec.whatwg.org/multipage/dom.html#referenced">referenced</a> by its relative position, e.g.,
"in the photograph above" or "as the next figure shows", then moving the figure would disrupt the
page's meaning. Authors are encouraged to consider using labels to refer to figures, rather than
using such relative references, so that the page can easily be restyled without affecting the
Some images contain text. I describe best practices for preparing pictures of text in [the "Pictures of text" section](#pictures-of-text). Only use pictures of text if the visual appearance of the text is an essential part of what you wish communicate. If the content of the text is also important, include a transcript.
Image transcripts aren't just useful for the visually impaired; they also help users relying on [machine-translation](#machine-translation), since translation tools rely on textual content. These users won't read alt-text; have an alternative way to discover a transcript.
If the image is a screenshot of text from a website, link to that website to allow users to read its contents in context; this can serve as an "image transcript" of sorts.
A <dfn>`longdesc`</dfn> attribute used to be another way to reference an image transcript. The `longdesc` attribute contained a hyperlink (often an anchor link) to a location with more information about an image. This attribute [has been obsoleted](https://html.spec.whatwg.org/multipage/obsolete.html#non-conforming-features) in the HTML Living Standard.
The recommended way to link to a transcript is by hyperlinking the image (i.e., wrapping it with `<a>`) or semantically grouping the image with its transcript. Put a short summary in the alt-text, and mention the availability of a transcript in a visible caption.
A [StackOverflow thread about comic transcripts](https://stackoverflow.com/questions/65564539/what-is-the-semantically-correct-way-to-include-transcript-from-a-comic) outlines a good approach to semantically group images and transcripts, and my approach is similar. I group an image, alt-text, and caption in a `<figure>` element and follow it with a transcript in a `<details>` element. I use `aria-describedby` to semantically link the figure and the transcript.
An image, alt-text, figure caption, and transcript combine to form a complex relationship that should be grouped together in a single landmark. I put all three inside an `<article>` with a heading, and give the group an `aria-label` that indicates the presence of the three sub-elements. Using an `article` landmark ensures that the figure and caption remain together as a single unit. The [html code](#xkcd-html) for the [xkcd comic earlier in the page](#infinite-scrolling) is a representative example.
{{<codecaptionlang="HTML">}} here's a simplified version of the HTML used to embed a comic in this article. Of course, I take care of most of the boilerplate with shortcodes. {{</codecaption>}}
Always remember that any color palette you define in your stylesheets is merely a suggestion. Any colors you don't define could fall back to arbitrary defaults; all colors you define could be overridden by the user agent or operating system.
Some users' browsers set default page colors that aren't black-on-white. For instance, Linux users who enable GTK style overrides might default to having white text on a dark background. Websites that explicitly set foreground colors but leave the default background color (or vice-versa) end up being difficult to read. The same phenomenon occurs on pages with text foregrounds with image backgrounds.
A second opinion: <spanitemprop="mentions"itemscopeitemtype="https://schema.org/TechArticle">{{<indieweb-personfirst-name="Chris"last-name="Siebenmann"url="https://utcc.utoronto.ca/~cks/"itemprop="author">}} describes this in more detail in {{<cited-workname="AWebColoursProblem"url="https://utcc.utoronto.ca/~cks/space/blog/web/AWebColoursProblem">}}</span>. In short: when setting colors, always set both the foreground and the background color. Don't set just one of the two.
Chris also describes the importance of visited link colors in <cite>[VisitedLinks<wbr>Usability](https://utcc.utoronto.ca/~cks/space/blog/web/VisitedLinksUsability)</cite>.
This is an unreadable screenshot of a [website promoting browser style overrides](http://bettermotherfuckingwebsite.com/) (specifically, the "A little less contrast" section). I had set my browser foreground and background colors to white and dark gray, respectively. The website overrode the foreground colors while assuming that everyone browses with a white background.
Black on white? How often do you see that kind of contrast in real life? Tone it down a bit, asshole. I would've even made this site's background a nice `#EEEEEE` if I wasn't so focused on keeping declarations to a lean 7 fucking lines.
Even if you set custom colors, ensure that the page is compatible with color overrides: elements shouldn't be distinguished solely by foreground and background color. [Technique C25](https://www.w3.org/WAI/WCAG22/Techniques/css/C25) for the <cite>Web Content Accessibility Guidelines (<abbrtitle="Web Content Accessibility Guidelines">WCAG</abbr>) 2.2</cite> describes how doing so can meet the WCAG 2.2's [Success Criterion 1.4.8](https://www.w3.org/WAI/WCAG22/Understanding/visual-presentation). Specifically, it describes using default colors in combination with visible borders. The latter helps distinguish elements from surrounding content without relying on a custom color palette.
This page's [canonical location](https://seirdy.one/2020/11/23/website-best-practices.html) is an example application of Technique C25 (and the related [Technique G148](https://www.w3.org/WAI/WCAG22/Techniques/general/G148)). It only uses non-default colors when a user agent requests a dark color scheme (using the `prefers-color-scheme` CSS media query; see the next subsection) and for lightening borders. Any image with a solid background may match the page background; to ensure that their dimensions are clear, I surrounded them with borders. I also set a custom color for the borders and ensure that the image backgrounds don't match the border colors. I included borders to break up some sections, since heading-based delineation is either unavailable or insufficient for them. When overriding color schemes, the page layout remains clear.
Color overrides go well beyond simple foreground and background color changes. Windows High Contrast Mode (<abbrtitle="Windows High Contrast Mode">WHCM</abbr>) is perhaps the best example. [WHCM makes advanced modifications to color palettes](#win-hcm): it colors elements with a user-specified palette, all according to semantic markup while ignoring ARIA overrides.[^11]
<abbrtitle="Windows High Contrast Mode">WHCM</abbr> leads the standardization process for the `forced-colors` CSS media feature, but it isn't the only implementation of the underlying idea. If you navigate to <samp>about:preferences</samp> in Firefox and activate the <samptranslate="yes">Colors</samp> button in the "Language and Appearance" section, you'll be presented with the option to override website palettes with [your own default colors](#default-colors).
Not all approaches completely discard a designer's specified color palette. The CSS Working Group is working on a specification for stylesheet processing in <spanitemprop="mentions"itemscopeitemtype="https://schema.org/TechArticle">{{<cited-workname="CSS Color Adjustment Module Level 1"extraName="headline"url="https://drafts.csswg.org/css-color-adjust-1/">}}</span>. The Chromium team's in-progress [auto dark mode](https://chromestatus.com/feature/5672533924773888) will use this specification to darken websites globally. Websites can opt out with the `color-scheme` property, but they really shouldn't have to: stylesheets should be robust enough to handle re-coloring.
{{<quotationid="win-hcm">}}
<blockquoteitemprop="text">
<ul>
<li>Win HCM is a collection of <strong>user defined color themes</strong> that overwrite your definitions in <abbrtitle="Cascading Style Sheets">CSS</abbr>.</li>
<li>It’s not about design but <strong>readability</strong>.</li>
<li>Some stuff will disappear in Win HCM, some won’t. Best advice is to use <strong>semantic <abbrtitle="Hypertext Markup Language">HTML</abbr></strong> to keep things visible.</li>
<li>You can use transparent <code>outline</code> to keep things visble like focus indicators and surface boundaries or use <code>currentColor</code> to maintain SVG <code>fill</code> colors in Win HCM.</li>
<li>You can use a special <strong>media query</strong> combined with special <strong><abbrtitle="Cascading Style Sheets">CSS</abbr> color key­words</strong> to give elements the user defined colors.</li>
{{<cited-workname="Accessibility Issues concerning Windows High Contrast Mode"url="https://accessabilly.com/accessibility-issues-concerning-windows-high-contrast-mode/">}}
If you do explicitly set colors, please also include a dark theme using a media query: `@media (prefers-color-scheme: dark)`. For more info, read the [`prefers-color-scheme` docs on MDN](https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-color-scheme). Dark themes are helpful for readers with migraines, photosensitivity (like me!), or dark environments.
If you include a `theme-color` directive in your document `<head>`, then recent browsers will automatically switch their default stylesheets to dark-mode. Unfortunately, some older browsers (like Firefox-ESR) don't support this directive, and WebKit's default dark stylesheet [has unreadable links](https://bugs.webkit.org/show_bug.cgi?id=209851). WebKit versions in the wild are often out of date, so a fixed stylesheet would need to be out for many years before I would consider using default dark stylesheets.
CSS filters such as `invert` are expensive to run, so use them sparingly. Simply inverting your page's colors to provide a dark theme could slow it down or cause a user's fans to spin.
Darker backgrounds draw less power on devices with OLED screens; however, backgrounds should never be solid black. White text on a black background causes halation, especially among astigmatic readers. Halation comes from the word "halo", and refers to a type of "glow" or ghosting around words. There has been some [experimental](https://www.laurenscharff.com/research/AHNCUR.html) and plenty of [anecdotal](https://jessicaotis.com/academia/never-use-white-text-on-a-black-background-astygmatism-and-conference-slides/) evidence to support this.
This image is an approximation of what halation looks like, cropped from <ahref="https://www.essentialaccessibility.com/blog/accessibility-for-people-with-astigmatism">Essential Accessibility</a>.
"Just disable dark mode" is a poor response to users complaining about halation: it ignores the utility of dark themes described at the beginning of this section.
If you can't bear the thought of parting with your solid-black background, worry not: there exists a CSS media feature and client-hint for contrast preferences called `prefers-contrast`. It takes the parameters `no-preference`, `less`, and `more`. You can serve increased-contrast pages to those who request `more`, and vice versa. Check section 11.3 of the W3C <spanitemprop="mentions"itemscopeitemtype="https://schema.org/TechArticle">{{<cited-workurl="https://drafts.csswg.org/mediaqueries-5/#prefers-contrast"name="Media Queries Level 5"extraName="headline">}}</span> specification for more information.
I personally like a foreground and background of `#eee` and `#0e0e0e`, respectively. These shades seem to be as far apart as possible without causing accessibility issues: `#0e0e0e` is barely bright enough to create a soft "glow" capable of minimizing halos among slightly astigmatic users, but won't ruin contrast on cheap displays. I also support a `prefers-contrast: less` media query which lightens the background to `#222`.
Color is a nuanced topic that deserves more attention than current guidelines give.
When setting colors, especially for a dark background, I recommend checking your page's contrast using Advanced Perceptual Contrast Algorithm (<abbrtitle="Advanced Perceptual Contrast Algorithm">APCA</abbr>) values. You can do so in an [online checker](https://www.myndex.com/APCA/) (requires JavaScript) or Chromium's developer tools (you might have to enable them in a menu for experimental preferences). Blue and purple links on a black background have much worse perceptual contrast than yellow or green links.
Note that [the APCA isn't fully mature](https://yatil.net/blog/wcag-3-is-not-ready-yet) as of early 2022. Until version 3.0 of the WCAG is ready, pages should also conform to the contrast ratios described in the WCAG 2.2's success criteria 1.4.3 (Contrast: Minimum, level AA) or 1.4.6 (Contrast: Enhanced, level AAA). This site's dark-mode stylesheet is an example of a palette that conforms to both the WCAG 2.2 AAA contrast requirements and APCA recommen­dations.
Yellow may have great contrast on dark backgrounds, but yellow and red can cause problems among [people who deal with overstimulation](https://www.tpgi.com/beyond-wcag-losing-spoons-online/); this includes [autistic people](https://www.experia.co.uk/blog/ultimate-guide-to-autism-friendly-colours/).
If you want to use yellow and red, lighten them up so that their color feels muted. This site's dark theme uses pale, washed-out yellow and pink for maximum contrast with minimal harshness.
Color palettes need to be effective for different types of vision deficiencies (e.g. color blindnesses) and screens. Color blindness is a far more nuanced topic than "the inability to see some colors". <spanitemprop="citation"itemscopeitemtype="https://schema.org/BlogPosting">{{<indieweb-personitemprop="author"first-name="Rob"last-name="Pike"url="http://herpolhode.com/rob/">}} describes his experience in {{<cited-workname="Color blindness"extraName="headline"url="https://commandcenter.blogspot.com/2020/09/color-blindness-is-inaccurate-term.html">}}</span>. Color blindness manifests in complex ways. Testing in grayscale is a great start, but it doesn't account for all kinds of color vision deficiencies.
Different screens and display-calibrations render color differently; what may look like a light-gray on a cheap monitor could look nearly black on a high-end OLED screen. Try to test on both high- and low-end displays, especially when designing a dark color scheme.
Color schemes should also look good to users who apply gamma adjustments. Most operating systems and desktop environments bundle a feature to lower the screen color temperature at night, while some individuals may select a higher one in the morning.
Some typographers insist that [underlined on-screen text is obsolete](https://practicaltypography.com/underlining.html)[^12], and that hyperlinks are no exception. I disagree.
Readers already expect underlined text to signify a hyperlink. Don't break fundamental affordances for aesthetics. Underlines are also necessary to distinguish the beginnings and ends of multiple consecutive links, especially among color-blind users.
A basic WCAG Level A requirement is for information to not be conveyed solely through color.
{{<quotation>}}
<blockquoteitemprop="text">
<p>Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or disting­uishing a visual element. (Level A)</p>
: Lossless PNG com­pression. It's like a parallelized version of [OptiPNG](http://optipng.sourceforge.net/) that also supports an implemen­tation of [ZopfliPNG](https://github.com/google/zopfli/blob/831773bc28e318b91a3255fa12c9fcde1606058b/README.zopflipng) compression
: Lossless or lossy JPEG com­pression. Note that JPEG is an inherently lossy format; the lossless features of `jpegoptim` only shrinks the size of existing JPEG files by removing unnecessary metadata.
: The reference WebP encoder; has dedicated lossless and lossy modes. Lossy WebP compression isn't always better than JPEG, but lossless WebP consistently beats PNG.
: The reference AVIF encoder, included in [libavif](https://github.com/AOMediaCodec/libavif)[^13]. AVIF lossless compression is typically useless, but its lossy compression is pretty unique in that it leans towards detail removal rather than introducing compression artifacts. Note that AVIF is not supported by Safari or most WebKit-based browsers.
I put together [a quick script](https://git.sr.ht/~seirdy/dotfiles/tree/3b722a843f3945a1bdf98672e09786f0213ec6f6/Executables/shell-scripts/bin/optimize-image) to losslessly optimize images using these programs. For lossy compression, I typically use [GNU Parallel](https://www.gnu.org/software/parallel/) to mass-generate images using different options before selecting the smallest image at the minimum acceptable quality. Users who'd rather avoid the command line while performing lossy compression can instead check out [Squoosh](https://squoosh.app/), a JavaScript app that bundles Web­Assembly-compiled encoders; I've heard good things about it.
You also might want to use the HTML `<picture>` element, using JPEG/PNG as a fallback for more efficient formats such as WebP or AVIF, but only if the size savings are more significant than a couple hundred bytes. More info in the [MDN `<picture>` docs](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/picture)
6. Create a lossy AVIF image from the cropped full-color PNG, and include it in the `<picture>` element if it's smaller than the WebP. If color isn't important, use the YUV400 color space.
In general, avoid loading images just for decoration. Only use an image if it has a clear purpose that significantly adds to the content in a way that text can't replace, and provide alt-text as a fallback. Any level of detail that isn't necessary for getting the point across should be removed by lossy compression and cropping.
If you want to include a profile photo (e.g., if your website is part of the IndieWeb and uses an [h-card](https://microformats.org/wiki/h-card)), I recommend re-using one of your favicons. Doing so should be harmless since most browsers will fetch and cache favicons anyway.
If you really want to take PNG optimization to the next level, try [Efficient Compression Tool](https://github.com/fhanau/Efficient-Compression-Tool).
this is a sample command to compress a PNG image using ImageMagick, `pngquant`, and `oxipng`. It shrinks the image, turns it grayscale, reduces the color palette, and then applies lossless Zopfli compression.
Some conventional wisdom for image compression doesn't hold up when compressing this aggressively; for instance, I've found that extremely aggressive dithering and PNG compression of small black-and-white images consistently surpasses JPEG compression.
Most resources on image optimization recommend considering progressive rendering. I don't recommend progressive rendering for below-the-fold images; if you optimize an image to just a few kilobytes, it should fully load in time. It's not worth the overhead for resources of less than 20 kb.
These resources also encourage authors to include different image variants for different viewport sizes, screen resolutions, and pixel densities. They often skip the caveats:
* Using different image files for different viewport sizes can cause the page to request more images as users re-size their window.
* Sending requests dependent on viewport and display character­istics is a fingerprinting vector, allowing servers to identify users by these properties.
Rather than create separate lanes for different users, I prefer making the defaults as inclusive as possible. A single image should look good under a variety of downscaling algorithms. It should be as small as it can be without losing essential information.
It might seem odd to create a lossless WebP from a lossy PNG, but I've found that it's often the best way to get the smallest possible image at the minimum acceptable quality for screenshots containing solid backgrounds.
Bright images on an otherwise dark page distract readers, especially readers like me with ADHD. The human iris adjusts to average amounts of light; an object far brighter than its surroundings causes eye strain even among readers with healthy vision.
A `<picture>` element allows selection of sources based on any CSS media query. When images have light backgrounds, I like to include dark variants to complement a dark stylesheet using an HTML `media` attribute: it selects a dark variant when the user has selected dark mode and is using a `screen` media type. Requiring the `screen` media type prevents selection of dark variants when printing. Printer paper is almost always white, so dark images could waste ink. Ink waste is a sensitive issue among many students: school printers sometimes charge students who exceed a given ink quota. Ask me how I know!
Light and dark variants of legacy formats (PNG, JPG, GIF), WebP, and AVIF can cause some of my `<picture>` imagesets to have up to six image variants. I could fully automate the process using my static site generator (Hugo) if I wanted to. Since I do want to inspect each image and compress to the minimum acceptable quality, I settled for partial automation using shell scripts and [a Hugo shortcode](https://git.sr.ht/~seirdy/seirdy.one/tree/master/layouts/shortcodes/picture.html).
I only recommend using SVG in images; avoid using them in embeds, objects, or directly in the body. Remember that users may save images, and open them in a non-browser image viewer with reduced SVG compatibility. To maintain maximum compatibility, stick a the subset of the [secure static processing mode](https://www.w3.org/TR/SVG/conform.html#secure-static-mode) of [SVG Static](https://www.w3.org/TR/SVG11/feature#SVG-static). Specifically, the subset that appears in the [SVG Tiny Portable<wbr>/Secure (<abbr title="Portable/Secure">PS</abbr>) spec](https://datatracker.ietf.org/doc/draft-svg-tiny-ps-abrotman/). SVG Tiny PS is a subset of [SVG Tiny 1.2](https://www.w3.org/TR/SVGTiny12/intro.html), which is a supported export format in most vector drawing programs. Ignore the elements specifically required for SVG Tiny PS; your image can be a standard SVG that only utilizes a tiny subset of the full SVG spec.
This advice might seem daunting, but it’s usually easy to use existing tools to generate an SVG Tiny file and manually edit it to support the SVG secure static mode. SVGs that conform to this subset should be compatible with Qt5's SVG implemen­tation, librsvg (used by Wikipedia and GNOME), and most operating systems' icon renderers.
Two tools that can optimize the size of an SVG file are [SVGO](https://github.com/svg/svgo) and the now-discontinued [svgcleaner](https://github.com/RazrFalcon/svgcleaner). Too much lossy SVG compression can sometimes _reduce_ the effectiveness of gzip and Brotli compression. Compress in moderation.
Page layout should be simple, predictable, consistent, familiar, and static. Avoid anything too unusual, since novelty could introduce a learning curve.
Keep the source order, DOM order, and visual order identical to ensure consistent behavior when navigating with the mouse, keyboard, assistive-technology, et al. Doing so should also result in a logical <kbd>Tab</kbd> order.
[Guideline 2.4 Navigable](https://www.w3.org/TR/WCAG22/#navigable) of the WCAG lists multiple criteria related to identifying and skipping sections of your pages, and for good reason:
* Users of [switch access controls](https://en.wikipedia.org/wiki/Switch_access) find it slow and frustrating to navigate long lists of focusable items.
* Screen readers make it difficult to consume poorly-organized content non-linearly.
* Clients that don't support CSS can't prioritize content using a supplied stylesheet.
The list goes on: nearly every reader reliant upon assistive technologies (<abbrtitle="assistive technology">AT</abbr>) struggles to skim through poorly-organized pages.
Related items need to be semantically grouped together. Group navigation links together in `<nav>` elements; sections under headings and landmarks; lists under `<ol>`, `<ul>`, or `<dl>`; etc. to give assistive technologies the means to skip over multiple items at once.
The first or second heading in the DOM, and the highest heading level, should be the page title marking the start of your main content (i.e. it should come after the site title, site navigation links, etc). Use elements like `<main>`, `<nav>`, and `<article>` to provide landmarks. If multiple navigation elements exist, give your main navigation element an `aria-label` or a heading.
Remember that not all landmarks are announced by screen readers; for instance, many screen readers don't announce the ending of a `<header>` element in an article. An `<hr>` element is a good way to force the ending of a landmark to be visible: it introduces a thematic break between sections that is visible to assistive technologies and user-agents that don't support CSS.
If this isn't possible, consider adding a "skip link" or two. Visually-impaired users generally prefer navigating by headings or landmarks, but screen reader beginners still benefit from a skip-link. Skip links are especially helpful when pure heading- and landmark-based navigation isn't optimal.
If your skip link toggles visibility states when focused, ensure that it doesn't move any existing content; see [the "Layout shifts" section](#layout-shifts) for more details. If it appears over existing content, it needs to have a solid background; if you set the background color, [set a foreground color too](#about-custom-colors).
Users of <abbrtitle="assistive technology">AT</abbr>s such as screen readers primarily navigate through landmarks, headings, and paragraphs. Sometimes they also navigate between links. Headings and link names need to be unique and descriptive enough to serve as navigational aids; paragraphs shouldn't be too long.
Think twice before placing important content immediately after skippable content such as nested landmarks, long code snippets, figures, and large lists. AT users who wish to skip content may jump directly to the next heading, glossing over anything between the skippable content and subsequent heading; this is especially common on mobile devices.[^14] When it makes sense to do so, place skippable content in its own sections and/or at the end of its parent section.
The remainder of the "Layout" section is possibly the most subjective part of this article, and the part with the most exceptions. Consider it more of a weak suggestion than hard advice. Use your own judgement.
A simple layout looks good at a variety of window sizes, rendering responsive layout changes unnecessary. Textual websites really don't need more than a single column; readers should be able to scan a page top-to-bottom, left-to-right (or right-to-left, depending on the locale) exactly once to read all its content. Verify this using the horizontal-line test: mentally draw a horizontal line across your page, and make sure it doesn't intersect more than one (1) item. Keeping a single-column layout that doesn't require responsive layout changes ensures smooth window re-sizing.
Achieving this type of layout entails using the WCAG 2.2 techniques <cite>[C27: Making the DOM order match the visual order](https://www.w3.org/WAI/WCAG22/Techniques/css/C27.html)</cite> as well as <cite>[C6: Positioning content based on structural markup](https://www.w3.org/WAI/WCAG22/Techniques/css/C6)</cite>.
Nontrivial use of width-selectors, in CSS queries or imagesets, is actually a powerful vector for [JS-free fingerprinting](https://matt.traudt.xyz/posts/2016-09-04-how-css-alone-can-help-track-you/). This is one of the reasons why I didn't recommend resolution- or dimension-aware imagesets in the [image optimization section](#image-optimization).
Exceptions exist: one or two very simple responsive changes won't hurt. The main anti-patterns are adjusting the relative order of elements, layout shifts dramatic enough to cause confusion, and making requests based on media queries that reveal fingerprintable information.
{{<codefigure>}} {{<codecaptionlang="CSS">}} the only responsive layout change on [my website](https://seirdy.one/) is a single CSS declaration to switch between inline and multi-line navigation links at the beginning of the page.{{</codecaption>}}
Sidebars are probably unnecessary, and can be quite annoying to readers who re-size windows frequently. This is especially true for tiling window manager users like me: we frequently shrink windows to a fraction of their original size. When this happens to a website with a sidebar, one of two things happens:
1. The site's responsive design kicks in: the sidebar vanishes and its elements move elsewhere. This can be quite CPU-heavy, as the browser has to both re-wrap the text _and_ handle a complex layout change. Frequent window re-sizers will experience lag and battery loss, and might need a moment to figure out where everything went.
2. The site doesn't use responsive design. The navbar and main content are now squeezed together. Readers will probably close the page.
Common items in sidebars include tag clouds, an author bio, and an index of entries; these aren't useful while reading an article. Consider putting them in the article footer or--even better--dedicated pages. This does mean that readers will have to navigate to a different page to see that content, but they probably prefer things that way; almost nobody who clicked on "An opinionated list of best practices for textual websites" did so because they wanted to read my bio.
Don't boost engagement by giving readers information they didn't ask for; earn engagement with good content, and let readers navigate to your other pages _after_ they've decided they want to read more.
As words-per-line decrease (by increasing zoom or narrowing the viewport), line lengths grow more varied. Justifying text will cause uncomfortable amounts of whitespace. In fact, <qcite="https://www.w3.org/TR/WCAG22/#visual-presentation">Text is not justified</q> is explicitly mentioned in the WCAG Success Criterion 1.4.8.
The WCAG recommends a max line length of 80 characters (40 characters for <abbrtitle="Chinese, Japanese, and Korean">CJK</abbr> languages) as [a AAA success criterion (SC 1.4.8)](https://www.w3.org/TR/WCAG22/#visual-presentation). However, studies seem to have mixed results; some people find it easier to read lines around 90 characters long, while others struggle beyond the 50-character mark. I think the WCAG over-simplified a complex issue. Then again, the AAA level was never intended to be a requirement.
Some of my links display long link-text; short line lengths can break these link texts too much, which can slightly hurt readability. Of course, narrow viewports will obviously make short line lengths non-negotiable. I decided to give article bodies a width of `38em`, which typically corresponds to just under 90 characters. I opted to use `em` instead of `ch` for consistency and for better compatibility with some uncommon browsers (NetSurf, Dillo, and others).
I also ensured that my site supports CSS overrides, window-resizing, zoom levels past 200%, and most "reading mode" implemen­tations. This should help accommodate a wide range of line-length preferences while still looking accessible enough by default.
{{<codefigure>}} {{<codecaptionlang="CSS">}} I opted to wrap all max-width rules in a media query to ensure that they only get called for the `screen` media type: {{</codecaption>}}
Not every phone has a giant screen: millions of people around the world use Web-enabled feature phones. The Jio Phone 2, for instance, is narrow enough to fall through a belt loop: it sports a screen that's just over 3.6 cm (1.44 inches) wide. Furthermore, some programs sport browser windows in sidebars (c.f. Mozilla's [side view](https://addons.mozilla.org/en-US/firefox/addon/side-view/), Vivaldi [Web Panels](https://help.vivaldi.com/desktop/panels/web-panels/)). Users who leverage floating or tiling windows rather than maximizing everything could use viewports of arbitrary dimensions.
Nowadays, even tiny smartwatches have built-in browsers; users who navigate to links in smartwatch message and email apps will use simplified browsers that fit on their wrists. Apple published a [video about WebKit on WatchOS](https://developer.apple.com/videos/play/wwdc2018/239/) (here's [a text summary of the video](https://brucelawson.co.uk/2018/the-practical-value-of-semantic-html/), starting at the "New types of devices" section); the Apple Watch Series 6 has a viewport that's 162 CSS pixels wide. Samsung Internet is a popular option for Wear OS users, whose viewports are often just 150 CSS pixels.
A single element wider than the viewport will trigger horizontal scrolling for the entire page. This is especially problematic for long pages that already require excessive vertical scrolling.
Long words, especially in headings, can trigger horizontal overflow. Test in a viewport that's under 240 pixels wide (<abbrtitle="Device Pixel Ratio">DPR</abbr>=1) and observe any words that trail off of the edge of the screen. Add soft hyphens to these words using the `­` entity.
Most modern browsers support the `hyphens` CSS 3 property, but full automatic hyphenation is usually an overkill solution with a naive implemen­tation. Automatic hyphenation will insert hyphens wherever it can, not necessarily between the best syllables. At the time of writing, humans are still better at hyphenating than most software implemen­tations. I only enable full hyphenation on the narrowest of viewports.
Users employing machine translation will not benefit from your soft hyphens, so don't expect them to always work as intended. Translation tools might also replace short words with long ones. Soft hyphens and automatic hyphenation are both flawed solutions, but I find soft hyphens to be less problematic.
Where long inline `<code>` elements can trigger horizontal scrolling, consider a scrollable `<pre>` element instead. Making a single element horizontally scrollable is far better than making the entire page scrollable in two dimensions.
Soft hyphens are great for splitting up text, but some text should stay together. The phrase "10 cm", for instance, would flow poorly if "10" and "cm" appeared on separate lines. Splitting text becomes especially painful on narrow viewports. A non-breaking space keeps the surrounding text from being re-flowed. Use the ` ` HTML entity instead of a space: `10 cm`. <spanitemprop="mentions"itemscopeitemtype="https://schema.org/Book">{{<cited-workname="Practical Typography"url="https://practicaltypography.com/">}}</span>[^12] describes [where to use the non-breaking space](https://briefs.video/videos/is-progressive-enhancement-dead-yet/) in more detail.
One exception to the rules from <cite>Practical Typography</cite>: don't use a non-breaking space if it would trigger two-dimensional scrolling on a narrow viewport. Between broken text and two-dimensional scrolling, broken text is the lesser evil. I personally set a cutoff at 2.5 cm (1 inch) at 125% zoom.
You should only use pictures of text when the visual presentation of the text is part of the information you're trying to convey. Always be sure to test how such an image looks on a narrow screen.
Images do not reflow their text. When the viewport is narrower than the image dimensions, two options arise:
1. Allow the image to exceed the viewport width, triggering two-dimensional scrolling for the whole page.
I already covered the first option in the prior subsection. If you expect viewers to read the text in the image and you don't link an image transcript, the second option isn't ideal.
The best compromise is to ensure that the image isn't too wide, and can support large text on a narrow viewport. Lines of text in images should contain as few characters as possible. For a good example, see the "[In defense of link underlines](#in-defense-of-link-underlines)" section.
Most browser default stylesheets were not optimized for narrow viewports, so narrow-viewport optimization is one of few good reasons to override the defaults. The best example of widescreen bias in browser stylesheets is indentation.
The HTML standard's section 4.4.4 [covers blockquotes](https://html.spec.whatwg.org/multipage/grouping-content.html#the-blockquote-element). It recommends placing a `<blockquote>` element inside a `<figure>` and citations in a `<figcaption>` to show a semantic relationship between a quotation and its citation.
Browser default stylesheets typically give `<figure>` elements extra margins on the left and right. `<blockquote>` elements have a large indent. Combining these two properties gives the final quotation an excessive visual indent, wasting precious vertical screen space. When quoted text contains list elements (`<ol>`, `<dl>`, `<ul>`), the indentation alone may fill most of a narrow viewport!
I chose to remove the margins in `<figure>` elements for quotations and code snippets. If you're reading this page with its own stylesheet enabled, in a CSS 2 compliant browser, you might have noticed the blockquotes on it have a minimal indent and a thick border on the left rather than a full indent. These two adjustments allow blockquotes containing bulleted lists to fit on most narrow viewports, even when wrapped by a `<figure>` element. Browsers that do not support CSS 3 properties such as `padding-inline-start` will render quoted text using default stylesheets (probably with an indent), which are perfectly usable if a bit inconvenient.
Another example: outside the Web, I prefer indenting code with tabs instead of spaces. Tab widths are user-configurable, while spaces aren't. HTML pre-formatted code blocks, however, are best indented with two spaces. Default browser stylesheets typically represent tabs with an excessive indent, which can be annoying on narrow viewports.
Designers often use figures to "break up" their content, and provide negative space. This is good advice, but I don't think people pay enough attention to the flipside: splitting up content with too many figures can make reading extremely painful on a short viewport. Design maxims usually lack nuance.
Small phones typically support display rotation. When phones switch to landscape-mode, vertical space becomes precious. Fixed elements (e.g. dickbars) become a major usability hazard. Ironically, the WCAG's own interactive Techniques reference is a perfect example of how fixed elements impact usability on short screens.
When filtering criteria on [the Quickref Reference page](https://www.w3.org/WAI/WCAG22/quickref/?currentsidebar=%23col_customize&showtechniques=134%2C124&levels=a&technologies=js%2Cserver%2Csmil%2Cpdf%2Cflash%2Csl), a dickbar lists active filters. I increased the zoom level; you may have to add more filters to fill the screen with a smaller font.
There's an ideal range somewhere between "cramped" and "spaced-apart" content. Finding this range is difficult. The best way to resolve such difficult and subjective issues is to ask your readers for feedback, giving disproportionate weight to readers with under-represented needs (especially disabled readers).
For now, I've decided to keep some indentation on list elements (`<ol>`, `<dl>`, `<ul>`) since I often fill them with links (see this article's [table of contents](#TableOfContents) for an example). This indentation provides important non-interactive negative space.
Readers with hand tremors depend on this space to scroll without accidentally selecting an interactive element; <spanitemprop="citation"itemscopeitemtype="https://schema.org/BlogPosting"><spanitemprop="publisher">Axess Lab</span> described the issue in {{<cited-workname="Hand Tremors and the giant button problem"url="https://axesslab.com/hand-tremors/"extraName="headline">}}</span>. Readers who double-tap to jump or zoom can't do so if there's no screen region that's "safe to tap". Having clearly distinguished links also helps users decide safe places to tap the screen; see the [section on link underlines](#in-defense-of-link-underlines) for more information.
Tap targets should be at least 44 pixels tall and wide [according to the WCAG](https://www.w3.org/TR/WCAG22/#target-size-enhanced); this is large enough to easily tap on a touch­screen. The WCAG makes an exception for inline targets, like links in a paragraph.
[Google has more aggressive tap-target recommen­dations](https://web.dev/tap-targets/): it recommends raising the limit 48 px with with 8 px gaps regardless of whether tap targets are inline, going so far as to make tap target size a ranking factor in search.
On lists without visible bullets, I dropped the default indentation. I had to find other ways to ensure adequate tap-target size and provide sufficient non-interactive space for readers with hand-tremors to scroll. Some examples:
- The [homepage posts list](https://seirdy.one/#posts) and the list of related articles at the beginning of [one of my posts](https://seirdy.one/2022/02/02/floss-security.html) separates links with non-interactive text descriptions
Increasing the line-spacing a bit will make tap targets larger and improve comprehension by readers with cognitive disabilities. A WCAG AAA Success Criterion is to allow 1.5 space units between lines; the <abbrtitle="Web Accessibility Initiative">WAI</abbr>'s Cognitive and Learning Disabilities Accessibility Task Force [recommends changing this Success Criterion's level](https://w3c.github.io/coga/extension/#changedlevels), finding it too important to be relegated to AAA status.
Reading modes leverage article extractors such as <spantranslate="no">[Readability](https://github.com/mozilla/readability)</span> (integrated into Firefox, Epiphany, Brave, Vivaldi, and others), [DOM Distiller](https://chromium.googlesource.com/chromium/dom-distiller/) (integrated into Chromium), and [Trafilatura](https://trafilatura.readthedocs.io/en/latest/) (powers a variety of tools and services). A host of other proprietary options exist: Diffbot powers services like Instapaper, Mozilla's Pocket has its own secret parsers, and countless "send to e-reader" services have amassed loyal users. Safari's proprietary fork of <spantranslate="no">Readability</span> has grown quite complex compared to upstream; Edge's Immersive Reader is [a mystery to me](https://techcommunity.microsoft.com/t5/discussions/documentation-on-huerestics-used-during-article-distillation-in/m-p/3266436), with [a problematic stylesheet](https://feedbackportal.microsoft.com/feedback/idea/e0d9b299-e3b6-ec11-a81c-000d3a7ce453).
I don't recommend catering to each tool's non-standard quirks. Studying their design reveals that they observe open standards, to varying degrees. <spantranslate="no">Readability</span>, DOM Distiller, and Trafilatura understand plain-old, semantic HTML (<abbrtitle="Plain-Old, Semantic HTML">POSH</abbr>).
POSH should be enough for most use-cases, but some authors want to go further. For example, they may want a byline or published date to show up in these modes.
Most extractors fetch these values using open standards for structured data. The most well-supported option is [microformats](https://microformats.org/wiki/microformats) (<spantranslate="no">Readability</span> is one of the few that supports the newer microformats2). Some support [schema.org](https://schema.org/) vocabularies in microdata or JSON-LD syntaxes, or [Dublin Core](https://www.dublincore.org/) vocabularies in RDFa. Most parse `<meta>` tags from the document `<head>`, but others don't due to misuse and overly aggressive <abbrtitle="Search Engine Optimization">SEO</abbr>.
Sorry, that was a lot of jargon for a single paragraph. Unfortunately, describing those terms is out of scope for this post. If you'd like to dive down this rabbit hole, read about the "Semantic Web".
Some reading-mode implemen­tations also support [DPUB-ARIA](https://www.w3.org/TR/dpub-aria-1.1/), but I'd caution against using ARIA when POSH is sufficient: "bad ARIA" can be far more harmful to screen readers than "no ARIA". Only use ARIA to fill in gaps left by POSH.
Again: avoid catering to non-standard implemen­tations' quirks, especially undocumented proprietary ones. Let's not repeat the history of the [browser wars](https://en.wikipedia.org/wiki/Browser_wars). Remember that some implemen­tations have bugs; consider reporting issues when one arises. More information about standard and non-standard behavior of reading modes is in the article <spanitemprop="mentions"itemscopeitemtype="https://schema.org/BlogPosting">{{<cited-workname="Web Reading Mode: The non-standard rendering mode"url="https://www.ctrl.blog/entry/browser-reading-mode-parsers.html">}} by {{<indieweb-personfirst-name="Daniel"last-name="Aleksandersen"url="https://www.daniel.priv.no/"itemprop="author">}}</span>.
Reading modes aren't the only non-browser user agents out there. Plain-text feed readers and link previewers are some other options. I singled out reading modes because of their widespread adoption and value. Decide which other kinds of agents are important to you (if any), and see if they expose a hole in your semantics.
Believe it or not, the entire world doesn't speak your website's languages. Browsers like Chromium, Microsoft Edge, and Safari have integrated machine translation to translate entire pages. Users can also leverage online website translators such as Google Translate or Bing. These "webpage translators" are far more complex than their plain-text predecessors.
Almost every word on your site can be re-written. Prepare for headings to change length, paragraphs to grow and shrink, or hyphenation to disappear. Your site's layout should make sense even when the length of each textual element is changed.
To ensure that pages get machine-translated properly, make proper use of semantic HTML. Daniel wrote about this topic too in <cite>[Semantic markup improves the quality of machine-translated texts](https://www.ctrl.blog/entry/html-semantic-improve-machine-translation.html)</cite>; I highly encourage giving his article a read.
Elements to pay close attention to include `<code>`, `<samp>`, `<var>`, `<kbd>`, `<abbr>`, and `<address>`. The semantic information conveyed by these elements supplies important context to translation algorithms.
Only after <abbrtitle="Plain-Old, Semantic HTML">POSH</abbr> is insufficient should you attempt to "override" behavior with the `translate` HTML attribute. Setting `translate="no"` or `translate="yes"` should override the behavior of standards-compliant translation engines. If you're unsure whether or not to use a `translate` attribute, search the relevant word or phrase on [Keybot](https://www.keybot.com/) to see how human translators approached it.
For example: machine translation will leave `<code>` and `<samp>` blocks as-is. Perhaps you could annotate comments within code with a `translate="yes"` attribute. However, translation engines should leave variables within those comments as-is.
[Google's style guide](https://developers.google.com/style/placeholders) recommends annotating format placeholders in code blocks with the `<var>` element; consider doing so and adding a `translate="yes"` attribute to placeholder values, at your discretion. For an example, check this article's code sample [describing my PNG optimization pipeline](#png-pipeline).
Consider the implications of translating between left-to-right (LTR) and right-to-left (RTL) languages. Do a search through your stylesheets for keywords like "left" and "right" to ensure that styles don't depend too heavily on text direction. Once you've cleared the low-hanging fruit, try translating the page to a language like Arabic.
Websites following this page's layout advice shouldn't need much adjustment. <spanitemprop="mentions"itemscopeitemtype="https://schema.org/TechArticle">{{<indieweb-personfirst-name="Ahmed"last-name="Shadeed"url="https://ishadeed.com/"appendString="’s"itemprop="author">}} {{<cited-workname="RTL Styling 101"url="https://rtlstyling.com/posts/rtl-styling/">}}</span> is a comprehensive guide to what can go wrong and how to fix issues.
Simple sites should err on the side of respecting default stylesheets. With rare exceptions, there are only two times I feel comfortable overriding default stylesheets:
1. Gently adjusting a parameter rather than completely changing an element's appearance. Typically, this involves adjusting dimensions.
2. Funda­mentally altering an element's appearance. I only feel comfortable doing this when the defaults are truly inaccessible, or clash with another accessibility enhancement I made.
My previous advice regarding line spacing and maximum line length fell in the first category. My approach to re-styling `<blockquote>` elements, adding borders, and using `sans-serif` fell in the latter category.
This section contains miscellaneous advice regarding the latter category of stylesheet overrides.
By default, most browsers render monospace text at a reduced size. If you want your monospace text to be readable, set its font family to `monospace monospace` (sic).
Font family alone is not enough to distinguish an element from its surroundings. For `<pre>`, `<code>`, and `<samp>` elements, I recommend supplementing the font family change with a soft border. As described in [the "Color overrides and accessibility" section](#color-overrides-and-accessibility), borders are preferable to background colors because they don't override the user-agent's preferred foreground and background colors.
Finally, it's important to distinguish `<kbd>` from `<code>`, `<samp>`, and regular body text.
The default focus indicators are hard to see in certain browsers (e.g. Firefox and WebKit), especially when the focused element already has a border. We can override them to make them more accessible.
On one hand, users who need enhanced focus visibility may override the default focus indicators in their browser preferences; I'd like to support such overrides. On the other hand, relying on these customizations would violate the "accessible by default" directive. This would exclude Tor Browser and fingerprinting-averse readers, as well as anybody who has to borrow a machine or browser they don't own or haven't customized yet. This is another one of the few areas where I'd recommend overriding browser default stylesheets.
The WCAG guidelines recommend making focus indicators 2 px thick in [Success Criterion 2.4.12](https://w3c.github.io/wcag/guidelines/22/#focus-appearance-enhanced). While this success criterion is only AAA-level, it's easy enough to meet and beneficial enough to others that we should all meet it.
You can use `:focus` and `:focus-visible` to highlight selected and keyboard-focused elements, respectively. Take care to only alter styling, not behavior: only keyboard-focusable elements should receive outlines. Modern browser stylesheets use `:focus-visible` instead of `:focus`; old browsers only support `:focus` and re-style a subset of focusable elements. Your stylesheets should do the same, to match browser behavior.[^15]
I do not re-style `:focus` when `:focus-visible` works, to match existing behavior. I also override `:focus` styling only on the subset of focusable elements that would normally show an outline. Based on the post <spanitemprop="isBasedOn"itemscopeitemtype="https://schema.org/BlogPosting">{{<cited-workname=":focus-visible and backwards compatibility"url="https://www.tpgi.com/focus-visible-and-backwards-compatibility/"extraName="headline">}} by <spanitemprop=authoritemscopeitemtype=https://schema.org/Organizationclass="h-card vcard p-author"><aitemprop=urlhref=https://www.tpgi.com/class="u-url url"><spanitemprop=nameclass="p-name">TPGi</span></a></span></span>.
This section focuses on ways to improve screen reader support that have not already been covered. The most important measures (semantic HTML, good alt-text and image context, correct spelling, etc.) have already been covered in previous sections.
<p>Try reading your screen through a drinking straw for an hour to get an idea of the limited context that a blind user has. You simply cannot scan the entire page at a glance with a screenreader - you have to listen to the structure of it carefully and remember all that, or read through the entire thing to find stuff, unless there are explicit associations such as longdesc.</p>
{{<cited-workname="longdesc Re: Clarification of rational for deprecation..."extraName="headline"url="https://lists.w3.org/Archives/Public/public-html/2008Feb/0061.html">}}
Some screen readers split up sections by HTML elements. This means HTML elements in the middle of a sentence will trigger pauses. The problem comes up frequently on sites that use excessive inline formatting.
This is especially concerning on my website, where I tend to hyperlink peoples' names (a common practice on the IndieWeb): making names possessive with an "apostrophe + s" creates pronunciation issues. "Seirdy's Home" could be read as "Seirdy. Link. S. Home" if the word "Seirdy" is a hyperlink.
A workaround is to use the "text" ARIA role to remove the semantics of elements. This workaround doesn't work in certain screen readers, including Orca, so don't count on it.
If you're unfamiliar with ARIA, always remember the <dfnid="first-rule-of-aria">First Rule of ARIA</dfn>: [No ARIA is better than Bad ARIA](https://www.w3.org/TR/wai-aria-practices-1.1/#no_aria_better_bad_aria). ARIA exposes a host of accessibility hazards when used improperly, so only use this approach when there's no good alternative.
Designers already test their websites with multiple browser engines to ensure cross-browser compatibility. Screen readers deserve the same treatment. Orca, VoiceOver, NVDA, Narrator, JAWS, TalkBack, and ChromeVox all have unique behavior. In addition, different browsers--even different Chromium forks--expose content to screen readers differently. You'll need to test multiple screen readers in multiple browsers, and keep track of updates to both. See why standards compliance is important?
Screen readers on touch screen devices are also quite different from their desktop counterparts, and typically feature fewer capabilities. Be sure to test on both desktop and mobile.
Screen reader implemen­tations often skip punctuation marks like the exclamation point ("!"). Ensure that meaning doesn't rely too heavily on such punctuation.
Screen readers have varying levels of verbosity. The default verbosity level doesn't always convey inline emphasis, such as `<em>`, `<code>`, or `<strong>`. Ensure that your meaning carries through without these semantics.[^16]
Default verbosity does, however, convey symbols and emoji. Use symbols and emoji judiciously, since they can get pretty noisy if you aren't careful. Use `aria-labelledby` on symbols when appropriate; I used labels to mark my footnote backlinks, which would otherwise be read as <samp>right arrow curving left</samp>. If you have to use a symbol or emoji, first test how assistive technologies announce it; the emoji name may not communicate what you expect.
Beware of `display` and `visibility` CSS properties; they can interfere with content reported to screen readers (see [quote from Steve Faulkner](#display-props)). Whenever you use one of those properties, re-test with screen readers just to be safe.
<p>Sometimes doing this can have an unintended effect of nuking the semantics of the elements, as conveyed to screen reading software, in the <ahref="https://www.tpgi.com/the-browser-accessibility-tree/">browser accessibility tree</a>. Screen readers and other assistive tech, in general, do not have direct access to the HTML DOM, they are provided access to a subset of information in the HTML DOM via <ahref="https://www.w3.org/TR/wai-aria-1.1/#dfn-accessibility-api">Accessi­bility APIs</a>. Sometimes what an element represents in the HTML DOM is not how it is represented in the accessibility tree.</p>
<p>If what is represented in the accessibility tree does not represent the devel­oper’s intended UI, it’s either (wittingly / unwittingly) the <strong>fault of the developer or the browser</strong>. But what we can be sure of, in these cases, is that it is <strong>not the fault of the screen reader</strong>.</p>
{{<cited-workname="Short note on what CSS display properties do to table semantics"url="https://www.tpgi.com/short-note-on-what-css-display-properties-do-to-table-semantics/"extraName="headline">}}
If your site is simple enough, it should automatically handle the vast majority of edge-cases. Different devices and browsers all have their quirks, but they generally have one thing in common: they understand <abbrtitle="Plain-Old, Semantic HTML">POSH</abbr>.
No matter how simple a page is, I don't think simplicity eliminates the need for testing. I outlined the need to analyze actual run-time behavior in [another post exploring how code alone doesn't give the full picture](https://seirdy.one/2022/02/02/floss-security.html).
In addition to standard testing, I recommend testing with unorthodox setups that are unlikely to be found in the wild. If a website doesn't work well in one of these tests, there's a good chance that it uses an advanced Web feature that can serve as a point of failure in other cases. Simple sites should be able to look good in a variety of situations out of the box.
Your page should easily pass the harshest of tests without any extra effort if its HTML meets basic standards for well-written code (overlooking bad formatting and a lack of comments). Even if you use a complex static site generator, the final HTML should be simple, readable, and semantic.
1. Evaluate the heaviness and complexity of your scripts (if any) by testing with your browser's <abbrtitle="just-in-time">JIT</abbr> compilation disabled.[^17]
7. Test keyboard navigability with the <kbd>Tab</kbd> key and [caret navigation](https://en.wikipedia.org/wiki/Caret_navigation). Even without specifying tab indexes, tab selection should follow a logical order if you keep the layout simple.
10. Read the (prettified and indented) HTML source itself and parse it with your brain. See if anything seems illogical or un­necessary. Imagine giving someone a printout of your page's `<body>` along with a whiteboard. If they have a basic knowledge of HTML tags, would they be able to draw something resembling your website?
14. Combine conversion tools. Combine an HTML-<wbr>to-<wbr>EPUB converter and an EPUB-<wbr>to-<wbr>PDF converter, or stack multiple article-extraction utilities. Be creative and enjoy breaking your site. When something breaks, examine the breakage and see if it's caused by an issue in your markup, or a CSS feature with an equivalent alternative.
15. Build a time machine. Travel decades--or perhaps centuries--into the future. Keep going forward until the WWW is breathing its last breath. Test your site on future browsers. Figuring out how to transfer your files onto their computers might take some time, but you have a time machine so that shouldn't be too hard. When you finish, go back in time to [meet Benjamin Franklin](https://xkcd.com/567/).
I'm still on step 14, trying to find new ways to break this page. If you come up with a new test, please [share it](mailto:~seirdy/seirdy.one-comments@lists.sr.ht).
{{<picturename="serenity"alt="Retro-looking web browser with bitmap fonts showing this article's \"Code snippet 7\"."sf=2>}}
<figcaption>
This page in the [SerenityOS](https://serenityos.org/) web browser. TLS 1.2 support isn't finished yet; I loaded it from a mirror with a compatible cipher suite.
* How to choose phrasings such that some meaning can be inferred without understan­ding numbers, for [dyscalculic readers](https://en.wikipedia.org/wiki/Dyscalculia). This is more applicable to posts whose main focus is not mathematical or quantitative.
* Ways to improve compre­hension by readers who struggle to understand non-literal language (certain cognitive disabilities, non-native speakers unfamiliar with idioms, etc.). I might wait until the <abbrtitle="Web Accessibility Initiative">WAI</abbr><cite>[Personali­zation Help and Support 1.0](https://w3c.github.io/personalization-semantics/help/index.html)</cite> draft specification matures and its vocabularies gain adoption before going in depth.
* Other accessible writing tips, maybe after I get a copy of <spanitemprop="mentions"itemscopeitemtype="https://schema.org/Book">{{<cited-workname="Writing Is Designing"url="https://rosenfeldmedia.com/books/writing-is-designing/">}} by {{<indieweb-personfirst-name="Michael"last-name="Metts"url="https://mjmetts.com/"itemprop="author">}} and {{<indieweb-personfirst-name="Andy"last-name="Welfe"url="https://www.andy.wtf/"itemprop="author">}}</span>. A relevant excerpt on writing accessibly is [on A List Apart](https://alistapart.com/article/standards-for-writing-accessibly/).
* Rules for descriptive link text, for screen reader navigation and for user-agents that display links as footnotes (e.g. some textual browsers with the `dump` flag).
* the Tor Browser (separate from "uncommon browsers" because of how "safest" mode is often incompatible with progressive enhancement and graceful degradation)
* Disabling JavaScript (overlaps with the Tor Browser)
* Non-default color palettes
* Aggressive content blocking (e.g. blocking all third-party content, frames, images, and cookies)
* User-selected custom fonts
* Stylesheet removal, alteration, or replacement
* Machine translators
Each of these may be dismissed as a "niche", especially given a profit motive (or worse, a growth imperative). Yet _many niches add up to a large population._ Every person who grows old becomes disabled; every long-distance traveller experiences poor connections.
Moreover, I don't think that the size of a disadvantaged population should always matter. I understand weighing population size if you have to make a trade-off between two conflicting special needs, but I don't think the aesthetic preferences of the majority are more important than supporting a disadvantaged minority.
Before you throw up your hands and decide you can't help everyone, take another skim through this page. Notice how much repetition exists between sections. _Nearly every bullet-point I listed benefits tremendously from plain-old, semantic HTML (<abbr title="Plain-Old, Semantic HTML">POSH</abbr>)_. If your page is usable with nothing but POSH, you've done half the work already.
The [250kb club](https://250kb.club/) gathers websites at or under 250kb, and also rewards websites that have a high ratio of content size to total size.
The [10KB Club](https://10kbclub.com/) does the same with a 10kb homepage budget (excluding favicons and webmanifest icons). It also has guidelines for note­worthiness, to avoid low-hanging fruit like mostly-blank pages.
My favorite website club has to be the [<abbr title="eXtreme HyperText Movement for Luddites">XHTML</abbr> Club](https://xhtml.club/) by {{<indieweb-personfirst-name="Bradley"last-name="Taunt"url="https://tdarb.org">}}, the creator of the original [1mb.club](https://1mb.club).
Also see [Motherfucking Website](https://motherfuckingwebsite.com/). Motherfucking Website inspired several unofficial sequels that tried to gently improve upon it. My favorite is [Best Motherfucking Website](https://bestmotherfucking.website/).
The [Web Bloat Score calculator](https://www.webbloatscore.com/) is a JavaScript app that compares a page's size with the size of a PNG screenshot of the full page content, encouraging site owners to minimize the ratio of the two.
One resource I found useful (that eventually featured this article!) was the "Your page content" section of <spanitemprop="citation"itemscopeitemtype="https://schema.org/TechArticle">{{<cited-workname="Your Personal Website"url="https://www.billdietrich.me/YourPersonalWebSite.html"extraName="headline">}} by {{<indieweb-personfirst-name="Bill"last-name="Dietrich"url="https://www.billdietrich.me"itemprop="author">}}</span>.
If you've got some time on your hands, I _highly_ recommend reading the <cite>[Web Content Accessibility Guidelines (WCAG) 2.2](https://www.w3.org/TR/WCAG22/)</cite>. The WCAG 2 standard is technology-neutral, so it doesn't contain Web-specific advice. For that, check the <cite>[How to Meet WCAG (Quick Reference)](https://www.w3.org/WAI/WCAG22/quickref)</cite>. It combines the WCAG with its supplementary [list of techniques](https://www.w3.org/WAI/WCAG22/Techniques/).
The WCAG are an excellent starting point for learning about accessibility, but make for a poor stopping point. Much of the content on this page simply isn't covered by the WCAG. One of my favorite resources for learning about what the WCAG _doesn't_ cover is [Axess Lab](https://axesslab.com/articles/).
I've learned about a great number of under­represented ways to browse from the Fediverse, particularly from [this subthread asking people to share](https://pleroma.envs.net/notice/AHqp3TEDFoyz0W4nbc) (requires JavaScript; [plaintext mirror](https://gopher.envs.net/pleroma.envs.net:7070/1/notices/AHqp3TEDFoyz0W4nbc)). Several responses informed updates to this page.
An early version of this article received useful responses when I [posted it to Lobsters](https://lobste.rs/s/akcw1m/opinionated_list_best_practices_for); I incorporated some feedback shortly afterward.
[^1]: Many addons function by injecting content into pages; this significantly weakens many aspects of the browser security model (e.g. site and origin isolation) and should be avoided if at all possible. For content such as public key fingerprints, I recommend setting a blank `sandbox` directive even if it means breaking these addons.
[^2]: Some addons will have reduced functionality; for instance, [Tridactyl](https://github.com/tridactyl/tridactyl) can't create an `<iframe>` for its command window. I consider this to be worthwhile since the most important functionality is still available, and because authors shouldn't feel compelled to support security weakening. I say this as someone who uses Tridactyl often.
[^3]: Here's an [overview of PE](https://en.wikipedia.org/wiki/Progressive_enhancement) and [my favorite write-up on the subject](https://whalecoiner.com/articles/progressive-enhancement).
[^4]: <spanitemprop="citation"itemscopeitemtype="https://schema.org/TechArticle">{{<cited-workname="High-Performance Browser Networking"url="https://hpbn.co/building-blocks-of-tcp/"extraName="headline">}} by {{<indieweb-personfirst-name="Ilya"last-name="Grigorik"url="https://www.igvita.com/"itemprop="url">}}</span> gives a great introduction to how TCP works, if you'd like more details.
[^5]: HPACK and QPACK header compression includes dictionaries containing common header names, and some common header values; HPACK lists them in "Appendix A" of <spanitemprop="citation"itemscopeitemtype="https://schema.org/TechArticle">{{<cited-workname="RFC 7541"url="https://datatracker.ietf.org/doc/html/rfc7541#appendix-A">}}</span>. If a header name or name-value pair one of these predefined table entries, its effective size can be reduced to a single byte. If a header has a value that isn't covered by the table, consider minifying it by removing unnecessary whitespace.
Remember that if your golden first kilobyte already lists all essential resources, these could be considered premature optimi­zations. Real bottlenecks lie elsewhere.
[^6]: Ironically, that page doesn't load the main text without JavaScript despite citing a JavaScript requirement as a downside. If you can't load the page, the same reasons are [outlined here](https://addyosmani.com/blog/infinite-scroll-without-layout-shifts/) in the "Accessibility concerns for infinite scroll" section.
[^7]: Firefox users [can enable "find as you type"](https://website-archive.mozilla.org/www.mozilla.org/access/access/type-ahead/) by toggling a preference in <samp>about:config</samp>. Chromium (and derivatives) users can [install an extension](https://github.com/Foxy/chrome-type-ahead); note that it requires full-page access and performs script injection to work.
[^8]: Iterating through a list of font names to see if each one is available on a user's system is a slow but effective way to determine installed fonts without being granted permission to use the Font Access API. [Browser­Leaks has a demo](https://browserleaks.com/fonts) of this approach. Warning: the page might hog your CPU for a while.
[^9]: Decoration is more than cosmetic. The [color overrides and accessibility](#color-overrides-and-accessibility) sub-section describes how some decorations, like borders, improve access­ibility.
[^10]: [WebAIM](https://wave.webaim.org/api/docs?format=html) and the [University of Illinois](https://fae.disability.illinois.edu/rulesets/IMAGE_4_EN/) recommends 100 characters; [Tangaru](https://www.tanaguru.com/en/) recommends an even lower limit of 80 characters.
[^11]: Since <abbrtitle="Windows High Contrast Mode">WHCM</abbr> sets colors independent of explicitly-defined ARIA roles, it's a good way to test adherence to [the First Rule of ARIA](#first-rule-of-aria).
[^12]: <spanitemprop="mentions"itemscopeitemtype="https://schema.org/Book">{{<cited-workname="Practical Typography"url="https://practicaltypography.com/">}}</span> only renders invisible text without JavaScript. You can use a textual browser, screen reader, copy-paste the page contents elsewhere, use a reader-mode implemen­tation, or "view source" to read it without enabling scripts. All of these options will ironically override the carefully-crafted typography of this website about typography.
I find <cite>Practical Typography</cite> quite useful for printed works, and incorporated a more moderate version of its advice on soft-hyphens into this page. With a few such exceptions, I generally find it to be poor advice for Web content.
[^13]: libavif links against libaom, librav1e, and/or libsvtav1 to perform AVIF encoding and decoding. libaom is best for this use-case, particularly since libaom can link against libjxl to use its Butteraugli distortion metric. This lets libaom optimize the perceptual quality of lossy encodes much more accu­rately.
[^14]: ATs typically let users navigate by headings, landmarks, paragraphs, and links. Most users prefer skipping article content with heading-based navigation. Keyboard users can bind different keys to different modes of navigation, but mobile users can only access one navigation mode at a time.
Mobile users wishing to temporarily switch modes have to stop, change their navigation mode, perform a navigation gesture, and switch back. Mobile users trying to skim an article don't always find this worth the effort and sometimes stick to heading-based navigation even when a different mode would be optimal.
[^15]: If you'd like to learn more, <spanitemprop="mentions"itemscopeitemtype="https://schema.org/BlogPosting">{{<cited-workname="A guide to designing accessible, WCAG-compliant focus indicators"url="https://www.sarasoueidan.com/blog/focus-indicators/"extraName="headline">}} by {{<indieweb-personurl="https://www.sarasoueidan.com/"first-name="Sara"last-name="Soueidan"url="https://www.sarasoueidan.com/"itemprop="author">}}</span> has far more details on making accessible focus indicators.
[^16]: Screen readers aren't alone here. Several programs strip inline formatting: certain feed readers, search result snippets, and textual browsers invoked with the `-dump` flag are some examples I use every day.
[^17]: Consider disabling the JIT for your normal browsing too; doing so removes whole classes of vulnera­bilities. In Firefox, navigate to <samp>about:config</samp> and toggle some flags under <code>javascript<wbr>.options</code>.
[^18]: LibreOffice can also render HTML but has extremely limited support for CSS. OnlyOffice seems to work best, but doesn't load images. If your page is CSS-optional, it should look fine in both.
