Common Web Accessibility Mistakes (And How to Avoid Them)

Web accessibility comes down to one question: can everyone actually use your website, including people who see poorly, who do not work with a mouse or who rely on a screen reader? If you have lost sight of that, you are shutting visitors out, and excluded visitors never become customers. In this article you will read the most common mistakes, why they hit your revenue, and how to fix them. Good news: the biggest wins sit in a handful of basic errors you can tackle today.

What exactly is web accessibility?

Web accessibility means your site is usable for as many people as possible, regardless of their disability or the device they browse with. The global frame of reference is WCAG (Web Content Accessibility Guidelines) from the W3C, built on four principles that are easy to remember through the acronym POUR: perceivable, operable, understandable and robust.

In practice it boils down to this: can someone who does not see colour tell your buttons apart? Can someone without a mouse complete your form? Does a screen reader understand what is on your page? Often the answer is no, and almost never on purpose.

Why does an inaccessible site cost you customers?

Very simply: whoever cannot use your site does not buy, does not fill in a form and does not get in touch. The barrier you put up is a wall for that visitor.

And this is not about a handful of people. The annual WebAIM Million study analyses the homepages of one million websites and found detectable WCAG errors on 95.9 percent of them in its most recent edition, averaging some 56 per page. These are not exotic edge cases. This is the norm.

Everything we do revolves around one question: does your website bring in customers? A beautiful site that shuts out part of your visitors leaks conversion rate you never see in your reports, because those people drop off quietly. That is exactly why accessibility belongs in every serious website development project and not as an afterthought.

Honestly: accessibility is nearly always just good UX for everyone, a point the W3C makes again and again in its explanation of the accessibility standards. Better contrast also helps the visitor in bright sunlight. Clear button text also helps whoever is in a hurry. You improve the experience broadly, not only for a niche group.

Which mistakes do you run into most often?

Most problems do not sit in advanced technology, but in basics that crept in while the site was being built. These are the classics.

Missing alt text on images

Alt text is a piece of HTML that describes what an image shows. A screen reader reads that text aloud to someone who cannot see the image. If the alt text is missing, the screen reader often simply reads out the file name, and for a chart or infographic that is worthless.

Watch the difference between empty and missing. A purely decorative image should have empty alt text (alt=""), which the screen reader neatly skips. An informative image should have descriptive alt text. Bonus: that alt text also helps your SEO.

Weak colour contrast

Just try reading white text on a yellow background. For a lot of people, every page with too little contrast feels like that. Light grey text on white, a brand colour as button text on a button that is just a touch too light: it looks sleek in the design, but it becomes unreadable for part of your visitors.

WCAG gives hard target figures here. Normal text needs a contrast ratio of at least 4.5 to 1, large text at least 3 to 1. With WebAIM’s free Contrast Checker you verify that in a minute. Look especially critically at your buttons and forms, because that is precisely where conversion happens.

Not operable with the keyboard

Not everyone uses a mouse. Many people navigate with the tab and space keys, sometimes via assistive software. Can you work through your entire site and complete every form with the keyboard alone? On more complex sites that often fails, because menus, pop-ups or home-made buttons never receive focus.

Two quick improvements: make sure everything you can click is also reachable with tab and has a visible focus outline, and add a “skip to content” link at the top of the page. That way a keyboard user does not have to tab through your entire menu on every new page.

Form fields without labels

You almost certainly have at least one form, if only on your contact page. But does every field have a real label? Placeholder text (the grey text that disappears the moment you type) does not count, because screen readers often skip it and the contrast is usually too weak.

Use a visible label tied to each field via the <label> element. Then everyone knows, human and screen reader alike, what belongs in each field. Forms are your conversion engine, so nothing here should be left vague. You can read more about that in our guide on the landing page.

Vague link text and unreadable tables

“Click here” says nothing, not to a visitor with a screen reader and not to Google. A screen reader sometimes reads out all links detached from their context, and a list full of “click here” and bare URLs is then unusable. Write link text that describes where you end up.

Data tables are another stumbling block. Screen readers often read tables in the wrong order. Keep tables simple and use correct headers (<th> with scope) so the structure stays clear. Wondering whether that table really needs to be a table? Then it usually does not.

What does the European Accessibility Act mean for you?

Since 28 June 2025 the European Accessibility Act (EAA) applies. That European regulation on web accessibility requires many companies to make their products and digital services accessible, certainly those offering online services or e-commerce to consumers. In practice it refers to the WCAG standards we discussed above.

We are not giving legal advice here, and not every organisation falls under the same obligations. But the direction is clear: accessibility is shifting from “nice to have” to “expected”. Have a specialist check whether and how the EAA applies to your situation. The good thing is that by tackling the mistakes above, you are moving the right way regardless.

How do you tackle this concretely?

You do not have to make everything perfect in one go. Work in this order and you will book visible wins quickly:

1. Do a quick manual check. Navigate your own site with the keyboard alone and turn your screen brightness down. You will feel the pain points immediately.
2. Grab the low-hanging fruit. Add alt text, fix the contrast on buttons and tie labels to form fields. These are often the biggest wins for the smallest effort.
3. Test with real tools. The W3C’s WCAG guidelines and free tools like the WebAIM Contrast Checker give you objective feedback.
4. Connect it to your goals. Accessibility that does not lead to more usable pages and more conversion is half a job. Combine it with your work on increasing conversion rate and your technical foundation such as Core Web Vitals.

Do not treat it as a one-off clean-up. Every new page or campaign can introduce new barriers, so make this checklist standard practice.

Frequently asked questions

Is web accessibility only for people with a disability? No. It helps everyone: visitors in bright sunlight, people on a slow connection, whoever is in a hurry or browsing on a small screen. It is simply good UX.

What is the difference between WCAG and the European Accessibility Act? WCAG is the technical guideline (the “how”). The European Accessibility Act is European regulation that determines which organisations must be accessible (the “who and why”), and in practice it refers to the WCAG standards.

Which mistake should I tackle first? Start with the three basics: alt text, colour contrast and keyboard operation. That is where the most impact sits for the least effort.

Does accessibility also help my SEO? Yes. Alt text, clear link text and clean HTML structure make your site more readable for both screen readers and search engines.

Do I have to rebuild my whole site to make it accessible? Usually not. Most mistakes are targeted fixes to existing pages. A full rebuild is only needed if the foundation is technically rickety.

Ready to make your site work for everyone?

Accessibility is not a box-ticking exercise, but the simplest way to convert the visitors you are quietly losing today into customers after all. We are a small team, so we move fast and always look beyond the design: we ask what it earns you. Book your free intake