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White on slate: contrast checker

White on slate means #ffffff text on a #334155 background, and the contrast ratio is 10.35:1. It passes every WCAG level, including AAA for normal text. Cool slate backgrounds are a common base for admin panels and documentation sites.

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.10.03:1AA pass
  • Aa Sample textDeuteranopiaNo green-sensitive cones.10.50:1AA pass
  • Aa Sample textTritanopiaNo blue-sensitive cones.10.31:1AA pass
  • Aa Sample textAchromatopsiaNo colour vision, only light and dark.10.36:1AA pass

rgb(255, 255, 255) · hsl(0, 0%, 100%)

rgb(51, 65, 85) · hsl(215, 25%, 27%)

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

Contrast ratio 10.35 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 white on slate

Is white on slate accessible?

Yes for most uses. #ffffff on #334155 reaches 10.35:1, above the 4.5 to 1 needed for AA normal text and the 7 to 1 needed for AAA.

Can I use white on slate for body text?

You can. At 10.35:1 the pair meets AA for body text, so white on slate is safe at 16 px and also meets the stricter AAA level.

How much margin does white on slate have?

For #ffffff on #334155 the ratio is 10.35:1, 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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Colour Placeholder GeneratorExact-size placeholder images in any colour, named for you.Open toolPalette from ImageDrop an image, get a palette you can paste into code.Open toolFavicon and App Icon GeneratorOne image in, every icon and the HTML snippet out.Open toolDevice Mockup GeneratorPut a screenshot in a clean device frame in seconds.Open tool

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.