Free Tool

WCAG Contrast Validator

Check if your colours are accessible.

Verify that your colour combinations meet the contrast ratios required by WCAG 2.2.

Text Color

Background Color

Contrast Ratio

21 : 1

Excellent — Meets AAA

AA — Normal Text Pass

AA — Large Text Pass

AAA — Normal Text Pass

AAA — Large Text Pass

Large sample text

Sample subtitle (24px)

This is a sample text at normal size (16px) to check the readability of this color combination according to WCAG 2.2 criteria.

Small text (14px) — Contrast is especially important at small sizes where readability is most affected.

WCAG 2.2 Quick Reference

Level AA — Normal text ≥ 4.5 : 1

Level AA — Large text (≥18pt / 14pt bold) ≥ 3.0 : 1

Level AAA — Normal text ≥ 7.0 : 1

Level AAA — Large text ≥ 4.5 : 1

Why does colour contrast matter?

Colour contrast is the most violated WCAG criterion on the web. According to the WebAIM Million 2024 report, 83.6% of home pages have at least one contrast error. This directly affects people with low vision, colour blindness, and users in high ambient-light environments.

WCAG 2.2 requires a minimum contrast ratio of 4.5:1 for normal text and 3:1 for large text (Level AA). For Level AAA, the ratios rise to 7:1 and 4.5:1 respectively. Our validator calculates these ratios instantly and tells you whether your colour combinations meet each level.

1

Minimum AA ratio: 4.5:1 (normal text) and 3:1 (large text, ≥18pt or 14pt bold).
2

Minimum AAA ratio: 7:1 (normal text) and 4.5:1 (large text).
3

83.6% of websites fail contrast criteria (WebAIM, 2024).
4

Free tool — no registration, unlimited use.

Differential Value

Why use this validator?

Instant Verification

Enter two colours (hex, RGB or name) and get the result instantly.

AA and AAA Levels

We tell you if you meet the legally required level (AA) and the optimal level (AAA).

For Designers and Devs

Ideal for validating colour palettes before implementation to avoid later corrections.

Frequently asked questions

Everything you need to know

Spanish (RD 1112/2018) and European (EAA) regulations require WCAG Level AA, which demands a ratio of 4.5:1 for normal text and 3:1 for large text (18pt regular or 14pt bold). Meeting these ratios ensures texts are legible for people with moderate low vision.

WCAG 2.2 (criterion 1.4.11) requires a ratio of 3:1 for non-textual interface components: form field borders, functional icons, informative graphics, etc. Only purely decorative elements are exempt.

This validator allows checking combinations of two colours. For a complete analysis of your corporate palette, request an accessibility audit where we analyse all combinations in your design system.

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WCAG Contrast Validator

Large sample text

WCAG 2.2 Quick Reference

Why does colour contrast matter?

Why use this validator?

Instant Verification

AA and AAA Levels

For Designers and Devs

Everything you need to know

Certifications and accreditations.