Search engine optimization is an important consideration for any web developer; if you want steady traffic, you need to follow appropriate SEO practices. At one time, that meant loading up pages with relevant keywords and hoping for the best. Unfortunately for some SEO experts (and fortunately for just about everyone else), that’s no longer the case.
In 2020, successful SEO means building a functional, efficient website with plenty of high-quality content. Google and other search engines use complex algorithms to prioritize sites that deliver great experiences for users — and to those algorithms, accessibility is a fundamental ranking factor.
Here's how a team of Google WebFundamentals instructors define accessibility:
Broadly speaking, when we say a site is accessible, we mean that the site's content is available, and its functionality can be operated, by literally anyone. As developers, it's easy to assume that all users can see and use a keyboard, mouse, or touch screen, and can interact with your page content the same way you do. This can lead to an experience that works well for some people, but creates issues that range from simple annoyances to show-stoppers for others.
Accessibility isn’t an afterthought, nor is it intended to improve the browsing experience for a small group of users. When properly implemented, accessibility ensures that users can interact with a website in a variety of ways without feeling frustrated or excluded.
For web developers, there’s an immediate, tangible benefit: Accessibility will make a website easier for search engines to read and interpret. After all, search engine spiders — the robots that crawl through a page and analyze content — aren’t typical users. They have trouble “seeing" text on images, they’re easily confused by complicated layouts, and they expect consistent page design. Optimizing a site for search often results in improvements to accessibility, and vice-versa.
Why better accessibility means better SEO
When a site is properly designed, search engines don’t miss out on content, and neither do human users. Adopting best practices for accessibility can dramatically improve rankings, and many of those best practices are fairly easy to implement. For example, consider these ranking factors.
Image alt text
Alt text provides a text description of images, a simple practice that leads to the image's information being made available to all users as well as search engines.
Text alternatives are a cornerstone of accessibility, but many site owners fail to implement them properly. Provide alt text for every meaningful image will allow search engines to interpret the information accurately while providing a usable site for people who use screen readers or refreshable Braille displays.
Avoid images of text
Webmasters should also avoid using images of text when it's possible. The Web Content Accessibility Guidelines (WCAG) discourage conveying information via images of text unless the image can be “visually customized to the user’s requirements" and using an image is “essential to the information being conveyed.”
For most sites, genuine text is preferable — adding text will supplement the page’s content and help search engines see important phrases, while users will enjoy a more accessible page.
Likewise, some users can’t see videos or hear audio content easily (or would simply prefer to access the content in another way). Transcriptions make a site more usable for people with vision, hearing, and cognitive impairments, and everyone at different times.
And while automatic transcription has come a long way, search engines aren’t great at interpreting the language in videos. AI tools require a great deal of processing power, and search robots prefer to work quickly by analyzing text. Transcribing a video will add a large amount of content to a page and make that content readable for search engines.
WCAG encourages a site to be easy to navigate, with clear instructions and consistent page organization. This helps everyone, including people with disabilities, to use the site naturally.
Adding headings, button labels, and other navigation elements will also send important signals to search engines, allowing them to determine what’s important on a page — and a predictable page with a limited number of elements will usually provide a better experience for everyone who accesses the site.
Semantic HTML elements clearly describe different parts of a web page. For example, the <article> HTML element indicates a blog post or other self-contained piece of content.
Replacing non-semantic tags with semantic tags adds important context for both search engines and users with screen readers.
Modern search engine algorithms don’t just look at keywords, they look at context — that’s part of the reason that a webmaster can’t repeat a certain phrase endlessly to obtain a high ranking.
Well-written content provides that context. Using simple, natural language on a page can establish that page as a valuable resource. Many users will find the site more functional as a result, since they won’t need to re-read confusing text or search for definitions in order to use the site.
Rising awareness of accessibility
As search engine algorithms change, they will almost certainly put more emphasis on accessibility. That’s partly due to changing demographics and a rising awareness of the experiences of people with disabilities.
Per one Pew Research Center survey, Americans with disabilities are about three times as likely as those without disabilities to say they "never go online," and they’re less likely to report a high level of confidence in their ability to use the internet. This isn’t a small number of people — the Centers for Disease Control and Prevention estimate that 26 percent of Americans have some form of disability, and since most people with disabilities are older adults, the number will likely rise as the baby boomer generation ages.
Accessible websites cater to every type of user (including search engine spiders) and provide a better overall experience. The benefits of an accessible approach are enormous — and for most developers, that approach is achievable with the right mindset.