Developer Utilities · Free tool
Contrast Checker
Check color contrast against WCAG AA and AAA targets for normal and large text. Live preview and pass/fail badges — free online tool with no download.
Normal text sample — The quick brown fox jumps over the lazy dog.
Large text sample — 24px bold
18.66px bold also counts as large
| WCAG AA — Normal (4.5:1) | Pass |
| WCAG AA — Large (3:1) | Pass |
| WCAG AAA — Normal (7:1) | Pass |
| WCAG AAA — Large (4.5:1) | Pass |
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What it does
Check a foreground/background color pair against WCAG 2.2 AA (4.5:1 for normal text, 3:1 for large) and AAA (7:1 / 4.5:1) contrast targets. Live preview shows sample normal and large text on the chosen background, with pass/fail badges on both levels.
Pair with color picker, color converter, and alt text helper for an accessibility pass.
Embed this tool on your siteShow snippetHide
Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.
<iframe src="https://freetoolarena.com/embed/contrast-checker" width="100%" height="720" frameborder="0" loading="lazy" title="Contrast Checker" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>How to use it
- Enter or pick foreground and background colors.
- Read the contrast ratio and AA/AAA badges.
- Nudge colors until both badges pass for your text size.
- Copy the final hex pair into your design system.
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Learn more
Guides about this topic
- How-To & Life · GuideHow to Check Color ContrastAudit colors against 4.5:1 AA and 7:1 AAA thresholds, including large text and dark mode. Test contrast instantly online with this free, no-sign-up tool.
- Using Our Tools · GuideHow to generate QR codesMake QR codes for URLs, WiFi, vCard, or text. Learn error correction and sizing, then generate your QR code online free with no sign-up in seconds.
- Using Our Tools · GuideHow to create a strong passwordGenerate a strong password instantly online for free. Build high-entropy passphrases following NIST 2026 rules with no download needed.
- Developers & Technical · GuideHow to encode and decode Base64Understand the 3-to-4 mechanic and 33% overhead for standard, URL-safe, and MIME Base64. Free online reference to avoid common mistakes, no download needed.
- Design & Media · GuideHow to choose a color paletteBuild accessible color palettes using HSL theory, monochromatic to triadic schemes, WCAG contrast checks, and dark mode tips. Free, no-download guide.
- Developers & Technical · GuideHow to use JWT tokens securelyImplement secure JWT authentication by choosing RS256, setting expiration, using httpOnly cookies, and preventing 'alg: none' attacks in your browser for free.
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