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Verify Color Accessibility Compliance with WCAG 2.1 Standards
A comprehensive tool for checking color contrast ratios against WCAG 2.1 accessibility guidelines. Ensure your designs are accessible to users with visual impairments.
The WCAG Contrast Checker helps you verify that your color combinations meet accessibility standards for users with visual impairments. The tool calculates contrast ratios using the official WCAG 2.1 formula.
Tip: The tool uses the relative luminance formula from WCAG 2.1, which accounts for the non-linear response of human vision to color intensity.
The color selection interface allows you to specify both foreground (text) and background colors in multiple ways.
Click the color swatch to open an interactive color picker. You can select colors visually or enter specific values.
Enter hex color values directly (e.g., #000000 or #FFFFFF). The input validates hex format in real-time.
#RRGGBB6-digit hex (e.g., #FF5733)#RGB3-digit hex (e.g., #F53 → #FF5533)Copy ButtonClick to copy the hex value to clipboardRandom Palette: Use the "Random Palette" button to generate random color combinations for inspiration or testing.
The contrast analysis section displays the calculated contrast ratio and provides detailed compliance information.
The contrast ratio is calculated as (L1 + 0.05) / (L2 + 0.05), where L1 is the relative luminance of the lighter color and L2 is the relative luminance of the darker color.
Recommendations: When your color combination doesn't meet WCAG standards, the tool provides specific suggestions for improving contrast.
The tool checks compliance against WCAG 2.1 guidelines, which define different levels of accessibility requirements.
The minimum level required for most web content.
Enhanced accessibility for situations requiring higher contrast.
Pass/Fail Indicators: Each compliance level shows a clear Pass (green) or Fail (red) badge, making it easy to see which requirements your color combination meets.
The live preview section shows how your color combination appears in real-world scenarios with adjustable typography settings.
Shows how headings appear with your color combination. Useful for testing section titles and emphasis text.
Demonstrates body text readability. Test longer passages to ensure comfortable reading experience.
Shows how buttons appear with inverted colors. Important for ensuring CTA buttons meet contrast requirements.
The saved colors feature allows you to store and manage color combinations for future reference.
Click "Save Combination" to store the current foreground and background colors. Up to 20 combinations can be saved.
Export all saved color combinations as a JSON file for backup or use in other projects.
Local Storage: Saved colors are stored in your browser's local storage and will persist between sessions.
Understanding WCAG contrast requirements helps you create inclusive designs that work for all users.
Adequate contrast ensures that text is readable for users with low vision, color blindness, or those viewing in challenging lighting conditions. It also helps in situations where displays have poor quality or are viewed at angles.
Many jurisdictions require websites to meet WCAG accessibility standards. Failure to comply can result in legal action and exclusion of users who rely on accessible design.
| Text Size | AA Minimum | AAA Enhanced |
|---|---|---|
| Normal Text | 4.5:1 | 7:1 |
| Large Text (18pt+) | 3:1 | 4.5:1 |
Ensure your website's text meets accessibility standards. Test different color schemes and find accessible alternatives to problematic combinations.
Verify that buttons, form inputs, and other interactive elements have sufficient contrast for all users to identify and use.
Validate brand color palettes for accessibility compliance. Identify which color combinations can safely be used for text.
Check colors used in documents, presentations, and PDFs to ensure they meet accessibility requirements for distribution.
Test color combinations for mobile interfaces where users may have varying display quality and lighting conditions.
Conduct quick accessibility checks during development or as part of comprehensive accessibility audits.
The tool uses the official WCAG 2.1 relative luminance formula for calculating contrast ratios.
Where each RGB component is linearized using gamma correction before calculating luminance.
Where L1 is the luminance of the lighter color and L2 is the luminance of the darker color.
Gamma Correction: The tool applies proper gamma correction (linearization) as specified in WCAG 2.1, ensuring accurate contrast calculations that match human visual perception.