Be vary of accessibility overlays
August 06, 2025 | AccessibilityWhen a site owner hears that there is a magical solution that fixes accessibility problems without the need to do anything on the site, it might sound perfect. A bit too perfect, maybe? At least for now, yes.
Some of the tool providers claim that you will conform to all accessibility requirements if you use the tool. But that, unfortunately, is not the case. No automated tool can detect all accessibility issues, and those who claim to do so are lying. The automated tools are getting better and better at finding accessibility problems, and hopefully, in the future, with the help of artificial intelligence or even some other future tools, we might actually be able to find all problems or tailor the web experience to each user's needs. But we aren't there yet.
What is an accessibility overlay?
If you haven't heard of an accessibility overlay, it is basically a third-party solution that can be added on top of your website. The idea behind these overlays is to provide a solution that doesn't require anything from the site owner. So no code changes or anything like that.
The overlay provides tools that are supposed to help fix accessibility issues. So the thought behind them are good but unfortunately the end result is usually not great. Many experts have tested several of these overlay tools and found that they cause accessibility issues.
The overlays tend to have redundant features
In many of the overlays there are features that are already provided by the browser, the operating system or some other software. And sometimes these features in the overlays cause problems for the existing features. I don't know how common or rare this type of thing is, but it's been mentioned in many places.
The benefit of using these existing tools is that they then apply to everything the user does. An overlay on a website is limited to only that website. So the user has to add the settings for all the sites separately if they want to use the provided overlays.
Some overlays probably have one or more beneficial features as well. I don't believe they are all bad. And I'm not trying to say the people behind the tools are necessarily bad either.
Potential user privacy issues
Some of the tools collect information about assistive technology use without people opting in. Use of any assistive technologies is thing many people don't necessarily want to disclose. So any such feature is a problem for user privacy. Disabilities can still be stigmatising, and people shouldn't be forced to share them.
I have also heard that some tools might add settings to user's cookies or similar and then add the same settings on all sites that use that tool. But with this the problem again seems to be not asking the user if they want this or not. While offering this type of a feature sounds good, especially for the user, the user always needs to be able to consent to the feature.
The overlays aren't a magical solution
I don't want to lump all the overlay services together or claim they are all terrible. But I do want you to be careful about these services.
If you are planning to get an overlay tool, ensure it doesn't cause any new accessibility issues. Ask questions and accessibility statement for the product before you spend your money on it. And remember that the tool will not make everything perfect, nor will it make you conform to the legal accessibility requirements. Currently, the best way to solve issues is still to remedy the issues on the website itself.