Check WCAG contrast, auto-fix failing pairs and simulate color blindness.
Approximate views computed with standard simulation matrices.
HEX, RGB & HSL palettes.
Percentages, ratios & change.
Count words, chars & case.
Built with privacy in mind. All processing happens entirely in your browser using open-source libraries.
WCAG contrast is the measured difference in luminance between text and its background. This checker computes the ratio, evaluates it against WCAG AA and AAA thresholds for normal and large text, and shows you exactly where your color pair stands.
Accessible design is not optional. When a pair fails, the auto-fix button adjusts the foreground color to reach a passing ratio, and the color-blindness simulator previews how your colors look to people with protanopia, deuteranopia and tritanopia.
Yes, free with no signup or limits.
It adjusts the foreground color toward a passing WCAG ratio without changing the hue family more than necessary.
Yes, all calculations happen locally in your browser.