Contrast Checker
WCAG contrast ratios, instantly.
Runs in your browserAbout
Contrast Checker measures the contrast ratio between a foreground and background color against both WCAG 2.2 (AA/AAA, normal and large text) and the newer APCA algorithm, showing a live text preview at both sizes so you can see the result, not just a number. It's built for checking whether real color pairs in a design will pass an accessibility audit before you ship them. Runs entirely client-side.
Frequently asked
- What's the difference between the WCAG and APCA scores?
- WCAG 2.2's ratio-based formula is the current legal and audit standard; APCA is a newer, more perceptually accurate algorithm expected in a future WCAG revision — the tool shows both so you can check against either.
- Does it check both normal and large text separately?
- Yes, WCAG's thresholds differ for normal versus large text, and both are shown, since a pair can pass for large headings while failing for body copy.