Accessibility Contrast Checker —
Free WCAG Test Online
Test your colours for web accessibility compliance. Free WCAG contrast checker — instant AA and AAA results, colourblind simulation, auto-fix. No signup, no limits.
Check Colour Contrast for Accessibility
Enter any two colours — get instant WCAG pass/fail results plus colourblind simulation and auto-fix suggestions.
Check Accessibility Contrast Free →Why Colour Contrast Is a Core Web Accessibility Requirement
Colour contrast is one of the most commonly failed accessibility criteria on the web. Roughly 1 in 12 men and 1 in 200 women have some form of colour vision deficiency. Millions more experience age-related vision decline or use screens in bright sunlight. Poor contrast excludes all of these users from reading your content clearly.
WCAG 2.1 Level AA — the standard referenced by ADA compliance, the European Accessibility Act, and most international accessibility laws — requires a minimum contrast ratio of 4.5:1 for normal text and 3:1 for large text. Every piece of text on your website needs to meet this standard independently.
What the Accessibility Contrast Checker Tests
The checker tests your colour pair against all four WCAG thresholds simultaneously: AA (4.5:1), AA Large (3:1), AAA (7:1), and AAA Large (4.5:1). It also simulates how your colours appear to users with Protanopia, Deuteranopia, and Tritanopia.
Use Auto-fix to get the nearest passing colour without manually adjusting and retesting. The live webpage preview shows how your colours look in a real layout — headings, body text, buttons, and links. After checking contrast, pair your accessible colours with the right typography using the free font pairings generator.