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How Are Web Accessibility And SEO Related?

| 7 minutes to read

What Is Web Accessibility?

Web accessibility is the overall term used for various web elements which combine to allow users access to your site & content. This is primarily aimed at those with some form of disability, but it also has crossover into overall user experience and SEO.

With around 15% of the world’s population having some form of disability, it’s important to take various accessibility aspects into account on your site. This has been pushed even more to the fore through the pandemic, as more users rely on online services rather than physical locations.

It’s written in law in many countries that government sites must meet accessibility requirements, but it is also highly recommended that private companies meet these requirements too. There have been various cases of companies being taken to court for lack of accessibility and there is the obvious lack of conversions which can result from inaccessible sites.

How Does This Relate To SEO?

As mentioned, many of the aspects of accessibility relate to user experience and the list below of common issues are often cited for enhancing the overall SEO and organic performance of a website.

From correct use of html structures through to structured data and transcripts, these SEO friendly optimisations also result in better accessibility. For the last few years, the onus has been on site responsiveness, speed and usability, so there is a good chance that the other accessibility features will be recognized ranking factors in the future.

Common Accessibility Issues

The points below are some of the main accessibility issues that can cause issues – from certain aspects not working as intended through to whole sites being inaccessible. Even just one or a single aspect of these affecting your site can block that potential 15% of traffic and conversions.


Overreliance On JavaScript


Always useful, but always causing headaches for search engine optimisation – JavaScript is great for users who rely on it’s delivery of visuals. For those with sight issues it can make websites basically blank unless alternatives are delivered.

Turning JavaScript off is simple enough to do, so you can quickly see your site how many screen readers will see it. They are getting better at this as search engine crawlers are too, but this is still an issue for many users.

No proper alternative when JavaScript is disabled gives a sliding scale of usefulness. We’ve seen sites which return no code at all, through to malformed menus and lack of imagery.

The latter is fine in many instances, but you might need to work more on your internal linking. Shops which lazily load content and products might inadvertently restrict user access to important pages.

Image Alt Text

Not just designed t give you that extra bit of SEO clout and to gain traffic from image searches, providing proper alt text gives reference and context to users who can’t see the images.

This is probably the prime example of where accessibility options have been co-opted for digital marketing reasons and they can often be spammy and not that great for users. Rather than ‘ticking a box’ so that all your images have alt text, make sure that it is actually useful. Describe the image and ideally do this in relation to each page it is on.

Headers & Structure

As mentioned previously, the basic html structures of a site can greatly help with indexing, layout and arranging information. This is true for screen readers, crawlers and general accessibility.

Header tags, paragraphs, tables, bullet points and structured data don’t just help you get that featured snippet or rich result, they allow full access to your site and the content within.

These will more often be development issues, but they cross over into SEO enough to merit attention. If your flashy page has an image table rather than < table > styling, it could result in a garbled mess.

Make sure that your header structure is sensible and properly implemented across the site. While they aren’t strictly required for SEO, they are good to see from an accessibility standpoint and worth working on for this alone.

Video Transcripts

Many of the accessible points rely on making images and content readable. As videos are a mixed media of sound and imagery, they are doubly open to inaccessibility.

Fixing this issue with transcripts, descriptions and other additional information is a great way to reach out to all users. Schema markup for videos can help with all of this without giving a visible difference to your site.

On third party sites such as YouTube you might be restricted to adding transcript and descriptions in the comments, but on your own site you can completely control what is on there.

Images & Text

Similar to the point made in the header and structure section above, if you deliver text content within an image, how can someone know what it says?

Alt text helps in a way, but this shouldn’t be used for greater amounts of text. If you’re creating header images or something else with text on then you should be adding this with html text, not purely graphical content.

This is slightly more development work, but as well as making it accessible, it can be used to decrease image sizes and increase page speeds.

Off-screen Elements

Setting things to off-screen used to be a go-to SEO tactic alongside keyword stuffing. After a while away, this is back to being a regularly common practice for responsiveness and for other content such as for screen readers.

Despite the fact this was a big no-no, the practice is generally accepted by search engines as fine to do as long as it isn’t malicious.

Interstitials & Cookie Notices

Interstitial pop-ups, cookie notices and other things to entice users back can be annoying at the best of times, and this frustration is increased for those with accessibility issues.

Without a clear X or other method of closing these pop-ups, they can render a whole site unusable. This is a relatively small number of sites, but it is critical when it goes wrong.

Intrusive Advertisements

Similar to the above, these are everyday annoyances which people live with, but even for the most able and experienced user they can prove difficult.

We’ve all experienced sites where you scroll down and then it’s solid advert for a screen or so. In these cases it can be hard to scroll without clicking the ad, and this can cause issues for users who navigate through non-conventional means, which leads to…

Keyboard Navigation

Interacting with sites is primarily done via the mouse and touch screens, but many users have adapted keyboards and other devices which replace these.

Most sites are coded so they can be navigated via arrows, tab, space, enter etc. You’ve probably accidentally done this when pausing a YouTube video with space only to fine it scrolls down because you haven’t selected the video.

This is all fine and works perfectly well – until it doesn’t. Sometimes users can be blocked out from navigating sites intentionally or otherwise. One famous example of this led to a case filed against Beyonce and her website as it was impossible to navigate for impaired users.

Contrast & Colours

Just under 10% of all people are colour blind, so with this and other conditions which can cause difficulty reading and interpreting sites, its important to bear this in mind.

Obviously this shouldn’t lead to all sites being monochrome and boring, but if you are in the design stages or looking at A/B testing with colours its good to consider this.

HTML Sitemaps

This can be seen as an archaic thing but having a link in the footer to an auto generated page is very little effort and real-estate to make life much easier for those who need it.

If you think having an xml sitemap is fine, then you should consider how would a user get to that page? Probably 99% of all xml sitemaps are not linked to from the main site, so these are functionally useless in terms of user accessibility.

Internal Linking

Internal linking has been mentioned a few times throughout this post, and it is important for SEO and accessibility.

Increased context, better access to deeper pages and an overall better user experience are all created when you include good internal linking. The ‘traditional’ SEO methods of internal linking are good for this, but it is worth noting that “click here” type links have a reduced context for accessibility purposes. You should include keywords in the anchor text to give context and to let users find these links easier.


From reading this you’ll see that SEO has become intrinsically linked to accessibility over recent years and will continue to do so.

There are numerous testing tools for accessibility, such as Wave – Web Accessibility Evaluation Tool and Google’s Lighthouse testing tool in Chrome. With testing tools you can often get erroneous results and good QA and testing is ideal, but make sure that accessibility is in mind throughout your site design, build and subsequent SEO work.

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Gary Hainsworth

Senior Organic Data Specialist

Gary is our technical SEO specialist and boasts more than 10 years’ experience in the industry. With in-depth knowledge on site migrations and all aspects of technical SEO, he’s a valuable asset to our team. Gary’s worked with the likes of the V&A, Warburtons, the NHS and the Lake District National Park. He has a passion for guitars too, be that playing them, modifying them or even building them. Gary has appeared in Startups Magazine, Portsmouth News and Southampton.gov.uk.

Gary Hainsworth Read more about Gary Hainsworth

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