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WCAG Color Contrast Checker (AA & AAA Standards)

Verify accessibility compliance between foreground text and background colors according to WCAG 2.1 AA and AAA standards.

  • 100% free
  • Files stay on your device
  • No sign-up, no watermark
Foreground (Text)
Background
Contrast Ratio
4.83:1
AA Normal
≥ 4.5:1
AAA Normal
≥ 7.0:1
AA Large Text
≥ 3.0:1
AAA Large Text
≥ 4.5:1
UI Controls
≥ 3.0:1

Live Sample Heading (Large Text)

This is standard body text previewing how your chosen foreground color reads against the background in compliance with W3C WCAG 2.1 accessibility guidelines.

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What is WCAG Color Contrast Checker (AA & AAA Standards)?

The Contrast Checker calculates the contrast ratio between a text colour and a background colour using the WCAG 2.1 formula and shows whether it passes AA and AAA for normal and large text. For example, white text on #dc2626 red scores about 4.8:1, which passes AA for normal text but not AAA. A live preview shows real text and a button in your colours, and Swap reverses foreground and background.

How to use WCAG Color Contrast Checker (AA & AAA Standards)

  1. 1

    Set the text colour

    Pick or type the foreground colour.

  2. 2

    Set the background colour

    Pick or type the background colour.

  3. 3

    Read the result

    See the ratio and AA/AAA pass or fail for normal and large text.

Frequently asked questions

What contrast ratio do I need?

WCAG AA requires 4.5:1 for normal text and 3:1 for large text (24 px, or 18.66 px bold). AAA requires 7:1 and 4.5:1.

Does contrast affect SEO?

Not directly, but accessible, readable pages keep visitors longer and are required by accessibility laws in many countries.

Does it support transparent colours?

Enter the final visible colour; transparency must be blended with the background first.

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