Color Contrast Checker & Optimizer
Test foreground text and background colors against official W3C WCAG 2.1 AA & AAA accessibility standards. Simulate color blindness, preview UI buttons, and auto-fix low-contrast colors with 1 click.
🎨 Color Inputs
HEX • RGB • HSL💡 1-Click Contrast Optimizer
Automatically nudge foreground brightness to guarantee WCAG AAA (7.0:1) compliance.
Accessible Engineering Headline (24px Bold)
High-velocity software engineering requires uncompromising design accessibility. Ensure all typography, buttons, and iconography remain crystal clear across every display device.
📚 Official WCAG 2.1 Contrast Standards Guide
Web Content Accessibility Guidelines (WCAG) 2.1 establish baseline luminance ratios to guarantee usability for users with low vision, color vision deficiencies, or aging eyesight.
Requires at least 4.5:1 for regular body text (<18pt / <14pt bold), and 3.0:1 for large text and UI components.
Requires at least 7.0:1 for regular text and 4.5:1 for large headings. Recommended for critical healthcare and enterprise systems.
Active input borders, radio toggles, charts, and standalone graphical icons must achieve at least 3.0:1 against adjacent colors.
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