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White on indigo: contrast checker

White on indigo means #ffffff text on a #4f46e5 background, and the contrast ratio is 6.28:1. It passes AA for normal text and for large text, but falls short of AAA for normal text. A popular modern interface accent that supports white labels comfortably.

Contrast ratio

Passes: AA normal text, AA large text, AAA large text, UI and graphics.

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.5.08:1AA pass
  • Aa Sample textDeuteranopiaNo green-sensitive cones.5.95:1AA pass
  • Aa Sample textTritanopiaNo blue-sensitive cones.5.57:1AA pass
  • Aa Sample textAchromatopsiaNo colour vision, only light and dark.6.28:1AA pass

rgb(255, 255, 255) · hsl(0, 0%, 100%)

rgb(79, 70, 229) · hsl(243, 75%, 59%)

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

Contrast ratio 6.28 to 1. Passes: AA normal text, AA large text, AAA large text, UI and graphics.

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 indigo

Is white on indigo accessible?

Yes for most uses. #ffffff on #4f46e5 reaches 6.28:1, above the 4.5 to 1 needed for AA normal text, though below the 7 to 1 needed for AAA.

Can I use white on indigo for body text?

You can. At 6.28:1 the pair meets AA for body text, so white on indigo is safe at 16 px.

How much margin does white on indigo have?

For #ffffff on #4f46e5 the ratio is 6.28:1, so it passes AA, but a slightly lighter or darker colour could drop it below 4.5 to 1. 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.