Accessibility Checker

An accessibility checker is a software tool that analyzes web content to identify potential barriers for people with disabilities, typically by testing against established guidelines such as WCAG or Section 508. Accessibility checkers range from browser extensions and command-line tools to full web services, and they vary widely in which rules they test and how they report results. A fundamental limitation of all automated checkers is that they can only definitively identify a subset of accessibility issues — estimates suggest around 30-40% of WCAG success criteria can be fully automated. Issues involving meaning, context, or equivalence (such as whether alt text accurately describes an image or whether link text is sufficiently descriptive) require human judgment. Well-designed checkers like AChecker distinguish between known problems, likely problems, and potential problems to make these limitations transparent. Common modern tools include axe, WAVE, Lighthouse, and Pa11y.