All free tools
Free tool

Is your text easy enough to read?

Enter two colours and see their WCAG 2.2 contrast ratio, and whether it passes for body text, large text and buttons at level AA and AAA.

Body text at sixteen pixels, as most of a page is set.

Large text, at eighteen points

7.06 to 1

  • Body text, level AAneeds 4.5 to 1, success criterion 1.4.3Passes
  • Large text, level AAneeds 3 to 1, success criterion 1.4.3Passes
  • Buttons, fields and icons, level AAneeds 3 to 1, success criterion 1.4.11Passes
  • Body text, level AAAneeds 7 to 1, success criterion 1.4.6Passes
  • Large text, level AAAneeds 4.5 to 1, success criterion 1.4.6Passes

Free, no account, and nothing you type leaves your browser.

How it works

The ratio is worked out exactly as WCAG 2.2 defines it: each colour's relative luminance, then the lighter one plus 0.05 divided by the darker one plus 0.05. It runs from 1 to 1, for two identical colours, to 21 to 1, for black on white.

Level AA asks for 4.5 to 1 for body text and 3 to 1 for large text, which WCAG defines as 18 point, or 14 point bold. Buttons, form field borders and icons a person needs to see need 3 to 1 against what is around them. Level AAA asks for 7 to 1 and 4.5 to 1. AA is the level accessibility law in Ireland is measured against; what WCAG AA asks of an Irish website explains how.

The ratio is cut to two decimal places, never rounded up, so a pair that just misses is never shown as a pass.

What it cannot tell you

  • It compares two flat colours. Text over a photograph or a gradient has to be checked against the part of the picture that gives the least contrast.
  • Contrast is one requirement among many. Headings, form labels, keyboard use and text alternatives for images matter as much, and no colour checker can test them.
  • Whether the law asks it of your website at all is a separate question, which the free Accessibility Act check answers.

Sources

  1. 1.Web Content Accessibility Guidelines (WCAG) 2.2: relative luminance, contrast ratio, and success criteria 1.4.3, 1.4.6 and 1.4.11 · World Wide Web Consortium

Read next

Where you stand on accessibility

The compliance assessment covers the rules that apply to you, accessibility among them, and gives you a record you can hand to a board, an insurer or a customer's purchasing team.

See the compliance assessment

All the free tools and checks