Make sure your text is readable for everyone. Enter a text colour and a background colour to see the exact WCAG contrast ratio and whether it passes the AA and AAA thresholds for normal and large text. Great for accessibility reviews and design systems.

Exact WCAG ratio

AA & AAA checks

Text & background preview

One-click copy

Use the tool now Step by Step

Trusted & free

It is completely free, private and requires no signup.

Set security headers

CSP, HSTS and X-Frame-Options harden your site.

Cache wisely

Use Cache-Control to speed up repeat visits.

Test on mobile

Verify headers and pages render well on small screens.

How it works

Enter a HEX value or use the colour picker for the text.

Do the same for the background — the ratio updates live.

See which WCAG levels pass and adjust the colours if needed.

Examples & Data

Foreground	Background	Ratio
#000000	#ffffff	21:1
#767676	#ffffff	4.54:1
#777777	#ffffff	4.48:1
#ffffff	#10b981	2.5:1

Small changes matter: #767676 passes AA, while #777777 just misses it.

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Help Center

Frequently Asked Questions

A number from 1:1 to 21:1 that measures the difference in luminance between two colours. Higher means more readable. Black on white is the maximum 21:1.

For normal text, AA needs 4.5:1 and AAA needs 7:1. For large text (18pt+ or 14pt bold) AA needs 3:1 and AAA needs 4.5:1.

Indirectly. Readable text improves user engagement and accessibility, which search engines reward. It is also a legal requirement in many countries.

No. Plenty of branded colours pass AA. Just check the ratio and darken or lighten as needed.

Bright Coding Network