Free Accessibility Tools
Check contrast, simulate color blindness, score readability — the working tools of WCAG compliance, free and running entirely in your browser.
About these tools
Roughly one in twelve men has a color vision deficiency, low vision becomes near-universal with age, and every visitor benefits from readable text — accessibility is mainstream engineering, not an edge case. These tools cover the checks designers and developers run most: exact WCAG 2.2 contrast ratios for a color pair or a whole palette, color-blindness simulation for images and palettes, readability scoring for plain language, and the px-to-rem conversion behind scalable text.
Everything runs on your device, which matters more here than usual: the color-blindness simulator accepts unreleased UI mockups and confidential documents precisely because they're never uploaded anywhere.
We hold ourselves to the same standards — this site ships with a skip link, visible keyboard focus, screen-reader announcements on results and errors, reduced-motion support, and text contrast we verified with these very tools.
Frequently asked questions
Are these tools based on the official WCAG formulas?
Yes — contrast uses the exact relative-luminance and ratio definitions from WCAG 2.2, verified against the specification's own reference values. Sources are linked on each tool.
Which tool should I start with?
The Contrast Checker — insufficient text contrast is the single most common accessibility failure on the web, and the fastest to fix.
Is my content private?
Yes. Images, palettes, and text are processed entirely in your browser — nothing is uploaded, which makes these tools safe for pre-release designs.
Looking for something else? Try Image tools · Dev & Text Utilities or browse all tools.