Contrast Checker
Check the contrast ratio between two colors against WCAG AA and AAA accessibility thresholds.
Sample text on this background
15.24:1
WCAG contrast ratio
AA — normal text (4.5:1) Pass
AA — large text (3:1) Pass
AAA — normal text (7:1) Pass
AAA — large text (4.5:1) Pass
Free to use, no sign-up, no limit on how many times you run it.More color tools
Overview
Low contrast between text and background makes content hard to read, especially for people with low vision. This tool calculates the exact WCAG contrast ratio for any two colors and checks it against the standard thresholds.
- Live sample preview of the actual color combination
- Checks against all four common WCAG thresholds at once
- Instant results as you adjust either color
How to use it
- 1Pick or enter a text color
- 2Pick or enter a background color
- 3Check the ratio against the pass/fail thresholds
Frequently asked questions
What's the difference between AA and AAA?
AA is the standard, widely-required accessibility level. AAA is a stricter, optional level for higher-contrast needs — most sites target AA compliance.
Why do large and normal text have different thresholds?
Larger text is inherently easier to read at lower contrast, so WCAG allows a lower ratio (3:1 for AA) for text at 18pt or larger, or 14pt bold, compared to 4.5:1 for normal-sized text.