Color Contrast Checker (WCAG)
Check WCAG 2.1 AA/AAA color contrast ratios for text, large text, and UI components. Live previews, APCA reference, accessible pair finder, and favorites.
Color Contrast Checker (WCAG)
Check color contrast ratios against WCAG 2.1 AA/AAA guidelines. Pick foreground and background colors, preview live text samples, and find accessible pairs.
ForegroundText
BackgroundSurface
Contrast ratio
14.68:1
APCA Lc 101.5 (reference)
AA Normal text
Requires 4.5:1
AA Large text
Requires 3:1
AAA Normal text
Requires 7:1
AAA Large text
Requires 4.5:1
AA UI Components
Requires 3:1
Frequently Asked Questions
What ratio do I need?
WCAG 2.1 AA requires 4.5:1 for normal text, 3:1 for large text (18pt or 14pt bold). AAA requires 7:1 and 4.5:1. UI components need >= 3:1.
How is the ratio calculated?
sRGB is gamma-corrected to linear, then relative luminance = 0.2126R + 0.7152G + 0.0722B. Ratio = (L1 + 0.05) / (L2 + 0.05) where L1 is the lighter.
What is APCA?
Accessible Perceptual Contrast Algorithm (for WCAG 3) — accounts for text weight, polarity, and spatial frequency. Shown as reference; WCAG 2 ratios remain the normative standard today.
Is the Color Contrast Checker (WCAG) free to use?
Yes, the Color Contrast Checker (WCAG) is 100% free with no registration, no hidden fees, and no usage limits. All processing happens locally in your browser, ensuring complete privacy.
Is my data safe with this tool?
Absolutely. The Color Contrast Checker (WCAG) processes everything client-side in your browser. No data is uploaded to or stored on any server. Your content remains private on your device at all times.
Does the Color Contrast Checker (WCAG) work on mobile devices?
Yes, the Color Contrast Checker (WCAG) is fully responsive and works on smartphones and tablets. You can use it on any device with a modern web browser -- no app download required.
Do I need to create an account to use this tool?
No account or registration is needed. Simply open the Color Contrast Checker (WCAG) in your browser and start using it immediately. There are no sign-up walls or usage restrictions.
What programming languages or formats does this support?
The Color Contrast Checker (WCAG) supports a wide range of popular formats and languages. Check the tool interface for the full list of supported options.
How do I use the Color Contrast Checker (WCAG)?
Simply enter your input in the provided field, adjust any settings to your preference, and the tool will process it instantly. You can then copy the result to your clipboard or download it.
Which browsers are supported?
The Color Contrast Checker (WCAG) works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera. For the best experience, use the latest version of your preferred browser.
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About Color Contrast Checker (WCAG)
Color Contrast Checker (WCAG) is a free, browser-based tool in our Developer Tools collection. Everything runs locally on your device — no uploads, no sign-up, and your data stays private.