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Contrast Ratio Checker

Check WCAG 2.1 color contrast compliance instantly. Includes color blindness simulation.

How it works

What is color contrast ratio?

Contrast ratio measures the difference in luminance between two colors. WCAG 2.1 defines minimum contrast ratios to ensure text is readable for people with low vision or color deficiencies.

WCAG compliance levels

AA Normal Text requires at least 4.5:1 contrast. AA Large Text (18px+ bold or 24px+ regular) requires 3:1. AAA is the highest standard at 7:1 for normal text and 4.5:1 for large text.

Why color blindness simulation matters

About 8% of men and 0.5% of women have some form of color vision deficiency. This tool simulates how your color choices appear to people with protanopia (red-blind), deuteranopia (green-blind), and tritanopia (blue-blind) — so you can verify your design works for everyone.

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