Foreground × background — compute the WCAG contrast live and see at a glance whether AA / AAA passes.
Text color
Background color
Contrast result
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Large text preview Aa
Normal text preview The quick brown fox jumps over the lazy dog. 0123456789
FAQ
What contrast ratio passes WCAG?
Normal text (<18pt): AA ≥ 4.5:1, AAA ≥ 7:1; large text (≥18pt or ≥14pt bold): AA ≥ 3:1, AAA ≥ 4.5:1.
How is the contrast calculated?
Per the WCAG 2.x formula: compute each color's relative luminance L (linearize the sRGB channels, then weight by 0.2126/0.7152/0.0722), then contrast = (Llight + 0.05) / (Ldark + 0.05), ranging from 1:1 to 21:1.
Is my data uploaded?
No. Computation is entirely local in your browser; nothing is sent anywhere.