Contrast Checker
Check WCAG contrast ratio between two colors for AA/AAA compliance.
Last updated August 26, 2026
The quick brown fox jumps over the lazy dog
17.74:1
About this tool
Web Content Accessibility Guidelines (WCAG) require a minimum contrast ratio between text and its background so content is readable for users with low vision or color blindness. This tool calculates the exact contrast ratio between two colors and checks it against the WCAG AA and AAA thresholds for both normal and large text.
WCAG contrast requirements
| Level | Normal text | Large text (18pt+/14pt bold+) |
|---|---|---|
| AA (minimum) | 4.5:1 | 3:1 |
| AAA (enhanced) | 7:1 | 4.5:1 |
Frequently asked questions
What counts as “large text” for the relaxed contrast requirement?
WCAG defines large text as 18pt (24px) regular weight or larger, or 14pt (18.66px) bold or larger — anything smaller must meet the stricter normal-text ratio.
Is AA or AAA compliance required by law?
It depends on jurisdiction and context — many accessibility laws and standards (like the ADA in the US, as interpreted by courts, or the EU's EN 301 549) reference WCAG 2.1 AA as the baseline, while AAA is generally treated as a stricter, optional target.