A11Y
WCAG Contrast Checker
Check color pair contrast ratio against WCAG AA and AAA thresholds. Live preview of sample text.
Runs entirely in your browser · Your input is never transmitted
The quick brown fox jumps over the lazy dog.
The quick brown fox jumps over the lazy dog.
The quick brown fox jumps over the lazy dog. Lorem ipsum dolor sit amet, consectetur adipiscing elit.
How to use
- Pick text and background colors.
- Read the ratio and WCAG pass/fail indicators.
Frequently asked
AA vs AAA thresholds?
AA: 4.5:1 for normal text, 3:1 for large text (18pt+ regular or 14pt+ bold). AAA: 7:1 normal, 4.5:1 large.
How is luminance calculated?
Per WCAG 2.1: convert sRGB to linear RGB, then weighted sum (0.2126 R + 0.7152 G + 0.0722 B).