Free Design tool
Colour Contrast Checker
Enter two hex colours to check the contrast ratio for normal and large text, plus interface components.
Your result
Use the example or enter your figures, then calculate.
Contrast is one accessibility check. Typeface, weight, placement and non-colour cues still matter.
How it works
Contrast ratio = (lighter relative luminance + 0.05) ÷ (darker relative luminance + 0.05).
Common questions
What ratio does normal text need?
WCAG AA specifies at least 4.5:1 for normal text and 3:1 for large text.
Does a passing ratio guarantee readability?
No. Check the result in its real context, including text size and font weight.
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