Free Color Contrast Checker — WCAG 2.1 Accessibility Tool
Check the contrast ratio between any two colors and verify WCAG 2.1 AA and AAA compliance for text, large text, and UI components. Results update instantly.
The quick brown fox jumps over the lazy dog
Sample body text at regular size for contrast evaluation.
Contrast Ratio
17.40 : 1
Normal Text
Body text under 18pt / 14pt bold
Large Text
18pt+ regular or 14pt+ bold
UI Components
Graphical objects and interface elements
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Built for creators and teams
How It Works
Enter your text color
Use the color picker or type any 6-digit HEX code (e.g. #1a1a1a) for your foreground text or element color. The preview updates immediately.
Enter your background color
Set the background color the same way. The live preview shows how your text will actually look against the background at both body and heading sizes.
Read the WCAG results
See the exact contrast ratio and whether your color pair passes AA and AAA compliance for normal text, large text, and UI components.
WCAG 2.1 Thresholds
| Level | Text Type | Min Ratio | Definition |
|---|---|---|---|
| AA | Normal text | 4.5 : 1 | Under 18pt regular or 14pt bold |
| AA | Large text | 3.0 : 1 | 18pt+ regular or 14pt+ bold |
| AA | UI components | 3.0 : 1 | Icons, borders, input outlines |
| AAA | Normal text | 7.0 : 1 | Enhanced accessibility standard |
| AAA | Large text | 4.5 : 1 | Enhanced accessibility standard |
Popular Use Cases
UI/UX Designers
Verify color palette combinations before finalizing designs. Catch contrast failures early rather than during developer handoff or accessibility audits.
Web Developers
Check CSS color choices meet accessibility standards while coding. Paste any HEX color pair and get an instant WCAG result without leaving your workflow.
Brand Teams
Ensure brand colors are usable in accessible UI. Identify which brand color combinations pass AA and which need a tint or shade adjustment for digital use.
Accessibility Auditors
Quickly check any color pair found during audits. The WCAG ratio and pass/fail status for all five criteria appear instantly for each combination tested.
Pro Tips
AA is the legal minimum for most web content
WCAG 2.1 Level AA (4.5:1 for normal text) is the standard required by ADA, AODA, and most international accessibility laws. Aim for AA as a baseline for every text element.
Use AAA for body text where possible
A 7:1 ratio (AAA) is ideal for body text — it ensures readability for users with low vision without requiring assistive technology. Use it for your main content text.
Test both light and dark mode
A color pair that passes in light mode often fails in dark mode, and vice versa. Check your text and background colors for both themes before shipping.
3:1 is enough for large headings
WCAG defines 'large text' as 18pt+ (24px+) regular or 14pt+ (18.67px+) bold. Large headings only need a 3:1 ratio to pass AA — giving you more brand color flexibility for headers.
Check placeholder text and disabled states
Placeholder text and disabled element colors are common contrast failures. Check these secondary states — not just your primary text colors — during your accessibility review.
Swap to test both directions
Contrast ratio is symmetric — swapping foreground and background produces the same ratio. Use the swap button to quickly test dark-on-light vs light-on-dark for the same color pair.
Next step
Contrast passing? Lock in your brand look
Accessible contrast is one part of a coherent visual system. Learn how to keep brand imagery consistent at scale, build a reliable palette with the color palette extractor, and apply it across every channel with a cross-platform strategy.
Common Issues & Solutions
Works Everywhere
Privacy, Security & Compliance
Your Privacy Matters
We don't store, log, or share any URLs or downloaded content. Your activity stays between you and the source platform.
Secure by Design
All requests are processed server-side over HTTPS. No client-side data collection or third-party trackers.
Legal Responsibility
Only download content you have rights to. Respect platform terms of service and copyright law.
This tool is intended for personal use and downloading content you own or have permission to download. Always respect the original creator's rights.
Frequently asked questions
Everything you need to know about using this tool.
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Startup Founder, Loopify
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Personal Brand Coach, Evolve With Sophie
“The hashtag recommendations alone save me 20 minutes per post. Multiply that by seven platforms and it adds up fast.”
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