Why an overlay won’t make your site accessible

In short

• An overlay is a widget that changes your site in the browser. It does not fix the site itself.
• It can’t reliably fix image descriptions, forms, error messages or keyboard access, so it can’t make you WCAG or EAA compliant.
• What works: an audit, real fixes in design and code, and testing with disabled people.

What an overlay is

An accessibility overlay is a piece of third-party code you add to your website, often with a single line. It shows a small icon on every page. When someone clicks it, they get a menu to change the text size, the contrast or the spacing. Many overlays also claim to fix problems automatically, using artificial intelligence.

The promise is simple: install the script, and your site is accessible and compliant. That promise is the problem.

What an overlay can’t fix

An overlay works on top of your pages after they load. It has to guess what your content means and how it should work. For the problems that matter most, guessing is not good enough. The Overlay Fact Sheet, signed by more than a thousand accessibility professionals, lists what automatic repair can’t do reliably:

• Image descriptions. A tool can say “a person at a window”. It can’t know that the photo shows your team in a workshop, or that a chart shows your prices going down.
• Forms. Labels, error messages and what happens to the focus after an error need to be designed. A script can’t know which field is required or what a good error message says.
• Keyboard access. If a menu or button only works with a mouse, a widget can’t reliably rebuild how it works.
• Content that changes. Modern sites update parts of the page with JavaScript. An overlay often can’t keep up with those changes.
• Documents and media. PDFs, videos and other files are not fixed by an overlay at all.

“Full compliance cannot be achieved with an overlay.”

Why it can make things worse

Many disabled people already have the tools they need: a screen reader, zoom, their own contrast or font settings. They know those tools well. An overlay adds a second layer on top, and the two can clash. Settings that worked yesterday suddenly behave differently on your site.

The widget itself is also part of your site. If it is hard to reach with a keyboard, or its menu is not announced well by a screen reader, you have added a new barrier instead of removing one.

And there is the cost you don’t see: while the overlay is in place, the real problems stay in the design and the code. Every new page is built with the same issues.

What the law says

Since 28 June 2025, the European Accessibility Act (EAA) asks many businesses in the EU, such as online shops, banks and transport services, to make their products and services accessible. For websites and apps, the European standard behind it points to WCAG, the Web Content Accessibility Guidelines.

WCAG conformance means meeting every success criterion, on every page. A widget on top of an inaccessible site does not change the site itself, so the problems are still there when someone checks.

Regulators have noticed. In January 2025, the US Federal Trade Commission ordered overlay maker accessiBe to pay 1 million US dollars over claims that its AI tool could make any website compliant.

What works instead

Real accessibility is less magic and more method. It also lasts longer, because every fix stays fixed.

1. See where you standAn audit with automated tools and manual checks: keyboard, screen reader, zoom, contrast. You get a clear list, in plain language, with what to fix first.
2. Fix it in the design and the codeReal labels, real image descriptions, real focus states. Fixed once, at the source, for every visitor.
3. Test with disabled peopleTools find part of the problems. People who use assistive technology every day find the rest.
4. Make it part of how you workAccessible components, a short checklist for every release, and a team that knows why it matters.
5. Be honest about itPublish an accessibility statement: what works, what doesn’t yet, and how people can reach you.

Not sure if the EAA applies to you? Take our free EAA check. It takes a few minutes, and you know where you stand.

Questions people ask

Does an overlay make my website WCAG compliant?

No. WCAG conformance means meeting every success criterion on every page, and an overlay can’t reliably fix image descriptions, forms, error messages or keyboard access.

Is an overlay enough for the European Accessibility Act?

No. The EAA asks for products and services that are accessible. A widget on top of the site does not change the site itself.

Can an overlay make my site harder to use?

Yes, it can. It can clash with the screen reader, zoom or contrast settings people already use, and the widget itself is not always accessible.

What should I do instead?

Start with an audit, fix the problems in the design and the code, test with disabled people, and build accessibility into how you work.

Sources

1. Overlay Fact Sheet, signed by accessibility professionals worldwide.
2. FTC order against accessiBe, US Federal Trade Commission, January 2025.
3. WCAG overview, W3C Web Accessibility Initiative.
4. European Accessibility Act, European Commission.