WCAG Color Contrast Accessibility Checker
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Why Color Contrast is the Foundation of Inclusive Design
Over 300 million people worldwide experience some form of color vision deficiency or low vision. Designing with high-contrast color palettes guarantees that your website buttons, navigation links, and alert banners remain readable for every user across mobile and desktop devices.
How Relative Luminance is Calculated
The W3C defines relative luminance on a scale from 0 (darkest black) to 1 (lightest white). The contrast ratio formula is (L1 + 0.05) / (L2 + 0.05), where L1 is the lighter color and L2 is the darker color.
Inspect & Generate Palettes with ToolSphere
- Visit our free Color Palette Generator tool.
- Lock your primary brand color and generate complementary, triadic, and analogous harmonies.
- Test against white and dark backgrounds with automatic WCAG AA/AAA scoring!
Ready to try this in practice?
Use our free WCAG Color Contrast Accessibility Checker directly on ToolSphere with 100% privacy guarantee.
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