Why is accessibility important for SEO?

Google prioritizes user experience and accessibility. Websites with poor contrast suffer higher bounce rates and shorter session durations, indirectly degrading search rankings.

Color Tools• a11y

WCAG Color Contrast Checker (AA & AAA)

Ensure your website design is accessible to all users, including those with visual impairments and color vision deficiencies. Test color pairs against official W3C WCAG 2.1 compliance standards for Normal Text, Large Text, and Graphical Components.

Processed locally on your device with complete privacy.

WCAG Contrast Checker

Everyday utilities, randomizers, time management, conversions, and e-commerce calculators.

Color Palette

Foreground Color

Background Color

Sample Text Preview: The quick brown fox jumps over the lazy dog.

WCAG Contrast Ratio

17.85 : 1

WCAG AA (4.5:1): PASSWCAG AAA (7:1): PASS

How to Use WCAG Color Contrast Checker (AA & AAA)

Pick Foreground & Background

Select text color and background color using HEX, RGB, or the visual color picker.

Review Contrast Ratio

View the exact mathematical ratio (e.g. 4.5:1, 7.1:1, or 12.4:1).

Inspect WCAG Badges

Check PASS/FAIL compliance badges for WCAG AA (Minimum) and WCAG AAA (Enhanced) standards.

About WCAG Color Contrast Checker (AA & AAA)

WCAG 2.1 Success Criterion 1.4.3 requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text (18pt or 14pt bold). Level AAA (Criterion 1.4.6) requires 7:1 for normal text. Proper contrast ensures readability under bright sunlight and for individuals with low vision.

Key Features

Exact mathematical relative luminance calculation: L = 0.2126R + 0.7152G + 0.0722B
Compliance evaluation for: WCAG AA Normal Text (4.5:1), WCAG AA Large Text (3.0:1), WCAG AAA Normal (7.0:1), and UI Components (3.0:1)
Live interactive preview simulating small body copy, bold headings, and button states
One-click 'Swap Colors' button to invert foreground and background
Smart Color Suggestion: automatically adjusts lightness to reach passing thresholds

Frequently Asked Questions

For standard body copy, WCAG AA requires a minimum ratio of 4.5:1. For large text (18pt+ or 14pt+ bold), the minimum ratio is 3.0:1.

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