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Colour contrast ratio (WCAG)
Check text and interface colours against WCAG contrast requirements.
Accessibility & inclusive productsHow it's worked out
- Ratio = (L1 + 0.05) ÷ (L2 + 0.05), with relative luminance L = 0.2126 R + 0.7152 G + 0.0722 B from linearised sRGB
- sRGB colours, no transparency
NoteLarge text is at least 18 point, or 14 point bold. Non-text interface parts and graphics need 3 : 1 under success criterion 1.4.11.
Source: W3C WCAG 2.2, success criteria 1.4.3, 1.4.6 and 1.4.11
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