Color Contrast Checker - Test WCAG Accessibility Compliance Online
Professional WCAG color contrast checker for web accessibility compliance. Test color combinations for AA and AAA standards, ensuring your designs are accessible to all users including those with visual impairments.
Free contrast checker with real-time validation and detailed accessibility information. No registration required - test unlimited color combinations instantly in your browser.
Sample Text
This is how your text will appear with the selected colors
What is WCAG?
WCAG (Web Content Accessibility Guidelines) are international standards for making web content accessible to people with disabilities.
Level AA Requirements
- Normal text: 4.5:1 contrast ratio
- Large text (18pt+ or 14pt+ bold): 3:1 contrast ratio
- Minimum requirement for most websites
Level AAA Requirements
- Normal text: 7:1 contrast ratio
- Large text: 4.5:1 contrast ratio
- Enhanced accessibility standard
Best Practices
Always aim for higher contrast ratios when possible. Test your color combinations with actual content and consider users with color blindness.
How to Use Color Contrast Checker
Select your foreground (text) color using the color picker or enter a HEX code
Select your background color using the second color picker or enter a HEX code
View instant contrast ratio calculation and WCAG compliance results in real-time
Test different color combinations until you achieve the desired accessibility level for your content
Color Contrast Checker Features
Color Contrast Testing Examples
Website Redesign for Accessibility Compliance
A web designer discovers their site's light gray text (#E5E5E5) on white background (#FFFFFF) fails accessibility tests. Using the contrast checker, they find a darker gray (#374151) that achieves AA compliance, improving readability for all users while maintaining their design aesthetic.
Mobile App Color Accessibility Audit
A mobile app development team tests their app's button colors and finds that their blue buttons (#3B82F6) on light backgrounds (#F3F4F6) don't meet AAA standards. They use the contrast checker to find a deeper blue (#1D4ED8) that achieves AAA compliance for better accessibility.
E-commerce Accessibility Improvement
An online retailer tests their product page colors and discovers that their green call-to-action buttons have poor contrast with their brand background. Using the contrast checker, they find alternative colors that maintain brand identity while achieving AA+ compliance for all users.
When to Use Color Contrast Checker
Web Design and Development
Essential for web designers and developers ensuring website accessibility. Test text and background color combinations to meet WCAG standards, making your content readable for users with visual impairments and color vision deficiencies.
Mobile App Development
Critical for mobile app developers creating accessible interfaces. Test color combinations for buttons, text, and interactive elements to ensure your app meets accessibility guidelines and provides good user experience in various lighting conditions.
UI/UX Design Projects
Perfect for UI/UX designers building accessible design systems. Validate color choices for different UI states, text sizes, and content types to create inclusive interfaces that work for all users regardless of visual abilities.
Digital Marketing Material Creation
Important for marketing teams creating social media graphics, email templates, and digital advertisements. Ensure your marketing materials have sufficient contrast for readability across different platforms and devices, reaching the widest possible audience.
Brand Identity Development
Useful for brand managers ensuring their brand colors work well together for accessibility. Test brand color combinations to create brand guidelines that are both visually appealing and accessible to all users.
Educational Content Development
Valuable for educators and content creators developing accessible learning materials. Test color combinations for presentations, PDFs, and online course materials to ensure educational content is accessible to students with visual impairments.
Understanding Color Contrast and WCAG Accessibility
Color contrast is the difference in brightness between foreground (text) and background colors. This contrast is measured using a ratio that determines how easily text and other content can be read by people with visual impairments. Higher contrast ratios indicate better readability and accessibility.
WCAG (Web Content Accessibility Guidelines) 2.1 establishes minimum contrast requirements for web content. Level AA requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text (18pt+ or 14pt+ bold). Level AAA requires higher contrast of 7:1 for normal text and 4.5:1 for large text.
Color contrast calculation uses the relative luminance of each color, which is the perceived brightness of a color. The formula accounts for human color perception differences, with some colors appearing brighter than their numerical values would suggest. This calculation ensures accurate accessibility testing.
Accessibility compliance considers multiple factors beyond contrast ratio, including text size, weight, and context. Large text has lower contrast requirements because it's inherently easier to read. Understanding these guidelines helps create truly accessible designs that work for everyone.
Common Contrast Testing Mistakes & Tips
Mistake
Only testing contrast on perfect screens
Tip
Test your color combinations on various devices and in different lighting conditions. Colors that work well on calibrated monitors may fail in bright sunlight or on older screens with poor color reproduction.
Mistake
Ignoring color vision deficiencies
Tip
Consider users with different types of color blindness when choosing colors. Some combinations that pass contrast tests may still be difficult for users with specific color vision deficiencies. Use color blindness simulators to test your designs.
Mistake
Relying only on automated contrast tools
Tip
Use contrast checkers as a guide, but also test with real users, including those with visual impairments. Automated tools can't capture all aspects of real-world usability and user experience.
Mistake
Not considering different text sizes and weights
Tip
Remember that accessibility requirements change based on text size and weight. Large text and bold text have lower contrast requirements. Plan your color combinations to work with your typography hierarchy.
Mistake
Forgetting interactive states and hover effects
Tip
Test all color combinations for different UI states including hover, active, focus, and disabled states. Ensure all interactive elements maintain sufficient contrast throughout their interaction states.
Mistake
Assuming light text on dark backgrounds is always better
Tip
Both light-on-dark and dark-on-light combinations can be accessible if they meet contrast requirements. Choose the combination that works best for your content, context, and user preferences, not just what's trending.
Color Contrast Checker Frequently Asked Questions
Is the color contrast checker completely free?
Yes, our color contrast checker is completely free with no registration required, no hidden fees, and unlimited testing. Check as many color combinations as you need without any restrictions.
What accessibility standards does the checker test against?
Our contrast checker tests against WCAG 2.1 (Web Content Accessibility Guidelines) standards, showing compliance levels for both AA and AAA requirements. We test for normal text, large text, and graphical object contrast requirements.
What is a good contrast ratio for accessibility?
For WCAG AA compliance, you need a minimum contrast ratio of 4.5:1 for normal text and 3:1 for large text. For AAA compliance, you need 7:1 for normal text and 4.5:1 for large text. Always aim for the highest ratio possible within your design constraints.
How does the contrast checker calculate contrast ratios?
Our tool uses the WCAG 2.1 formula that compares the relative luminance of two colors. It accounts for human color perception differences, making the calculation more accurate than simple color value differences. The calculation ensures results match official accessibility standards.
Can the checker suggest better color combinations?
Yes, our contrast checker includes color suggestions that can help you find more accessible alternatives. When a combination fails accessibility tests, the tool provides recommended colors that maintain your design intent while improving contrast and readability.
Do I need to test every color combination in my design?
You should test all text and background combinations, especially for important content and interactive elements. Focus on body text, headings, links, buttons, and form elements. Creating a consistent color system that passes accessibility tests helps ensure your entire design is accessible.
Is my color data secure when using the contrast checker?
Absolutely. All contrast calculations happen locally in your browser using JavaScript. No colors or test results are ever sent to our servers. Your accessibility testing and color work remain completely private and secure.
What if I need to maintain brand colors that have poor contrast?
When brand colors have accessibility issues, consider using them for decorative elements rather than text, or create variations that maintain brand identity while improving contrast. You can also use the problematic colors with sufficient text size and weight to meet accessibility requirements.