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Black on white: contrast checker

Black on white means #000000 text on a #ffffff background, and the contrast ratio is 21.00:1. It passes every WCAG level, including AAA for normal text. The maximum possible contrast, used by print and by most long-form reading pages.

Contrast ratio

Passes every WCAG level.

Large text, 24 px bold

Normal text at 16 px. The quick brown fox jumps over the lazy dog, and the contrast should be easy to read.

Button

Colour-blindness preview

How the pair may look with each type of colour vision, and whether normal text still passes AA. This is an approximation for design checks, not a medical test.

  • Aa Sample textProtanopiaNo red-sensitive cones.21.00:1AA pass
  • Aa Sample textDeuteranopiaNo green-sensitive cones.21.00:1AA pass
  • Aa Sample textTritanopiaNo blue-sensitive cones.21.00:1AA pass
  • Aa Sample textAchromatopsiaNo colour vision, only light and dark.21.00:1AA pass

rgb(0, 0, 0) · hsl(0, 0%, 0%)

rgb(255, 255, 255) · hsl(0, 0%, 100%)

  • AA normal text4.5:1Pass
  • AA large text3:1Pass
  • AAA normal text7:1Pass
  • AAA large text4.5:1Pass
  • UI and graphics3:1Pass

Contrast ratio 21.00 to 1. Passes every WCAG level.

Fix suggestions

Already at 4.50:1 or better. Nothing to fix.

Similar colour pairs

How to check any pair

  1. Enter two colours

    Type a hex, rgb or hsl value, use the colour picker, or pick any pixel on your screen where the browser supports it.

  2. Read the verdict

    The ratio and five badges update as you type. Each badge says pass or fail for one WCAG level.

  3. Check the specimen

    See your colours as normal text, large text, a button outline and an icon, exactly as a visitor would.

  4. Fix a failing pair

    Pick a target ratio and apply the closest passing colour. Only lightness changes, so your hue stays recognisable. A colour-blindness preview shows how the pair holds up for other eyes.

  5. Share or compare

    Copy the result as text, CSS or an image, or copy a link that opens the same colours. Switch to grid mode to compare up to eight colours at once.

Questions about black on white

Is black on white accessible?

Yes for most uses. #000000 on #ffffff reaches 21.00:1, above the 4.5 to 1 needed for AA normal text and the 7 to 1 needed for AAA.

Can I use black on white for body text?

You can. At 21.00:1 the pair meets AA for body text, so black on white is safe at 16 px and also meets the stricter AAA level.

How much margin does black on white have?

For #000000 on #ffffff the ratio is 21.00:1, so there is room to soften either colour and still pass AA. Test any change in the checker before you ship it.

Next step

Put your colours on a favicon

Once your brand colours pass, turn one of them into a favicon and app icon set, with the manifest and the HTML to paste, in a single ZIP.

Make a favicon
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About these tools

Small tools, made by Sifency

Sifency is a small studio that builds themes, plugins and web apps. These tools began as the things we kept needing ourselves, so we tidied them up and left them open for everyone. There is nothing to sign up for.