Website accessibility is first and foremost about making sure visitors with specific accessibility requirements can ‘view’ your website, whether that means visually or using a screen reader to read the page aloud.

In principle, accessibility is an issue that affects human visitors to your site. The search robots typically ‘fetch’ your pages as if they were viewing them in a regular web browser, so you might think any accessibility measures you implement would have little to no impact on your search ranking.

However, you might be surprised by how some accessibility features of websites can help with organic SEO performance by providing the search robots with extra information about your page, optimised for your target keywords.

The caveat to this is the same that applies to all on-page SEO techniques: optimising website content for better search rankings should not come at the expense of user experience. So, make sure that your accessibility features still provide good value to human visitors who need to use them.

Why is there a link between website accessibility and SEO?

If you stop to think about how the search engine robots crawl your site, it is quite easy to understand why accessibility and SEO are linked.

As yet, search robot AI is still not advanced enough to fully understand the content of visual media like images and videos. Object recognition is improving, but computers are a long way from understanding the context of an image without plain text descriptions.

Many accessibility features provide this context in the form of plain text attributes that are usually hidden from view. For example, often when you point your cursor to an image on a web page, a pop-up text caption appears that describes the image.

These captions don’t come from anywhere – they are defined in the page code using the ‘title’ and ‘alt’ attributes to add the additional text information to the image element. You can fully customise the text, which means you can include any preferred SEO keywords.

When a search robot crawls your page, it sees all of those attributes and the repetition of those keywords can further reinforce the SEO benefits. Therefore, it is good practice to choose a particular keyword and mention it in both the title and alt text attributes.

Types of website accessibility

There are many different ways to implement website accessibility, and they can positively affect your SEO performance in different ways too, for example:

Plain Text

Using more plain text helps visitors who use screen readers. It can also allow partially sighted visitors to use their browser text size setting or zoom function to make the text bigger on their screen.

For the search engines, it means more of your page content is easy to crawl and index, with the best visibility of your primary keywords. You can reinforce this further using headings to structure your page content, make it easier to read and flag up the keywords.

Images and Video

Make full use of alt and title attributes when including multimedia elements on your page. These should be descriptive enough so that visitors using a screen reader can understand what the element is displaying, even if they cannot see it at all.

This descriptive element is an excellent opportunity to repeat primary keywords by including them in the alt and title attributes, an on-page text caption below the element, and even by putting them in the filename of your image or video file if possible.

Element Size

Make sure page elements – especially hyperlinks and navigation buttons – are large enough that a visitor with poor dexterity can tap them on a touchscreen without too much difficulty.

Clear and clutter-free navigation is a feature of mobile-friendly website design too, which is something the search engines increasingly prioritise in their rankings. So large links and buttons with proper spacing in between should help avoid any negative results in your next mobile SEO audit too.

More ways to add page context

There are several technical ways to add context to pages within your HTML code, which can be beneficial to visitors using accessibility aids like screen readers.

Accessible Rich Internet Application (ARIA) landmarks tell screen readers which part of the page is navigation, which part is the main content, which parts are interactive forms or search boxes, and so on. They can help visually impaired visitors to skip straight to the main page content or the navigation bar.

Some microformats can be beneficial for accessibility too. You can even use metadata to tell the browser if an image meets the minimum level of contrast or if an audio file contains speech that is easy to hear – ask your web designer or SEO agency if you’re not sure what microformats are.

Best practice for website accessibility

There are plenty of things you can do to improve website accessibility that might not directly impact your search rankings, but which by making your site visible to more of your visitors, can help to reduce your bounce rate.

Just some examples of best practice for website accessibility include:

  • Good contrast between text and background colours for better visibility.
  • Clear fonts for headings and paragraph text to improve legibility (including for visitors with dyslexia).
  • Use text links for navigation so screen reader software can tell visitors where a link can take them.

Accessible website design maximises your potential audience – so even without moving up in the rankings, you still increase your potential customer base. But with the added benefit of aligning with many best practices for SEO as well, accessibility delivers on all fronts.

Finally, be consistent in your use of accessibility features. Adopt accessible page templates across all areas of your website and ensure anyone publishing new content includes image alt attributes.

Just one inaccessible page can lead some users to abandon your website, so consider auditing your existing content and make sure that it all meets with present-day web standards and methods. Doing this can give you the best platform to publish new pages in the future.