Contrast Checker
Check WCAG AA/AAA contrast ratios for accessibility compliance.
The quick brown fox
Sample text in normal size — check legibility here.
:1
Contrast ratio
About the Contrast Checker
This tool calculates the contrast ratio between two colors using the WCAG 2.1 relative luminance formula and reports whether the combination meets the WCAG AA (4.5:1 for normal text, 3:1 for large text) and AAA (7:1) accessibility standards. Results update live as you adjust the colors.
Sufficient color contrast ensures text is readable for people with low vision or color blindness. It's a legal requirement in many jurisdictions and a core part of WCAG, the Web Content Accessibility Guidelines. Use this checker when choosing text and background colors for websites, apps, and digital documents.