What is accessibility drift?
Your website changes every day. Accessibility drift is what happens to its accessibility between assessments.
Most organizations check their website's accessibility at a point in time: an audit, an assessment, or a scan before a launch. Then the website keeps changing.
New pages go live. Content editors publish updates. A shared component changes, and the change reaches hundreds of pages at once. Each change can introduce new barriers or bring back ones you already fixed. That gradual change is accessibility drift.
Why drift is hard to see
An assessment shows you one moment. By the time the next one happens, it's hard to tell what changed, when it changed, and why. Issues that came back look the same as issues that were never fixed.
How to catch it
- Monitor your whole website on a schedule, not only a sample of pages.
- Compare each scan with the last one, so you see what's new, what's fixed, and what came back.
- Look for patterns. When many pages fail the same way after a release, the cause is often one shared component.
- Keep the history, so you can connect a change in your results to a change on your website.
Automated monitoring finds many common issues, but not all of them. Pair it with manual testing, especially testing with assistive technology such as screen readers.