The world's smartest color contrast tool. Get AI-powered suggestions and instant WCAG and APCA compliance.
Test your color combinations with WCAG 2.2 and APCA standards
Choose your text and background colors
The quick brown fox jumps over the lazy dog
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Web Content Accessibility Guidelines 2.2
Requires 4.5:1
Requires 3:1
Requires 7:1
Requires 4.5:1
Advanced Perceptual Contrast Algorithm
Excellent
Suitable for all text sizes
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Automatically extract dominant text and background colors
JPG, PNG, WEBP • Max 10MB
See how your colors look across different font sizes and weights
The quick brown fox jumps over the lazy dog
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The quick brown fox jumps over the lazy dog
0123456789 !@#$%^&*()
The quick brown fox jumps over the lazy dog
0123456789 !@#$%^&*()
The quick brown fox jumps over the lazy dog
0123456789 !@#$%^&*()
The quick brown fox jumps over the lazy dog
0123456789 !@#$%^&*()
The quick brown fox jumps over the lazy dog
0123456789 !@#$%^&*()
The quick brown fox jumps over the lazy dog
0123456789 !@#$%^&*()
The quick brown fox jumps over the lazy dog
0123456789 !@#$%^&*()
WCAG contrast ratios have been the industry standard for decades, establishing clear numerical requirements: 4.5:1 for normal text (Level AA), 3:1 for large text, and 7:1 for enhanced accessibility (Level AAA). These ratios are legally recognized and widely required for compliance. APCA, by contrast, uses a perceptual model based on contemporary color science that accounts for how the human eye actually processes contrast considering factors like text size, color properties, and viewing distance. APCA produces Lc values (ranging from 0 to 106) that are more predictive of actual readability, especially for non black on white color combinations. While WCAG remains the legally required standard globally, APCA often provides more nuanced guidance for edge cases and alternative color schemes. Many modern accessibility tools now support both metrics, allowing designers to verify compliance with established regulations while also testing against next generation perceptual standards.
When text and background colors are too similar, some people can't see the words clearly. Color blindness and low vision make small color differences hard to notice for example, blue text on a dark red background can look almost invisible. Low contrast also makes buttons, links, and form fields hard to spot. That's more than a small annoyance: it can stop people from using a site, and it can break legal accessibility rules in many places.
Contrast checkers automatically find text, buttons, and other elements that don't meet WCAG rules. Fixing those problems before a site goes live lowers the chance of complaints or lawsuits. In short: they turn a vague "make it accessible" task into clear, testable fixes you can track and fix.
Good contrast makes content readable for more people. Use WCAG rules to meet legal requirements, consider APCA for extra real-world readability checks, and build contrast testing into your design and development process so accessibility isn't an afterthought.
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