GUIDE · 2026-07-22
How to use the WCAG Color Contrast Checker
Test whether a color pair stays readable for normal and large text. The result follows “Contrast = (lighter relative luminance+0.05) ÷ (darker luminance+0.05)” and is designed for situations such as check body text accessibility. Inputs are handled immediately in your browser with no account required.
How it works
Contrast = (lighter relative luminance+0.05) ÷ (darker luminance+0.05)
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Useful examples
- Check body text accessibility
- Test button-label contrast
- Compare brand color pairs
Frequently asked questions
What is the difference between AA and AAA?
For normal text, AA requires 4.5:1 while AAA requires 7:1.
What counts as large text?
WCAG generally treats 24 px regular text or about 18.66 px bold text as large.