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Colour contrast per WCAG 1.4.3

Text must differ sufficiently from the background. WCAG 2.2 success criterion 1.4.3 requires at least 4.5:1 for normal text, at least 3:1 for large text (from 24 px, or from 18.66 px bold).

Common mistakes

Light grey body text on white (often only 2.5–3.5:1), placeholder text in form fields, light button text on a mid tone, link colour too close to the text colour.

How to fix it

Darken the text colour or lighten the background until the value fits. Never use colour as the only distinguishing feature — underline links too, name states too.

Not affected

Purely decorative elements, disabled controls and logos do not have to meet the contrast requirement.

How a11yglass helps

The free scan checks the delivered HTML and CSS for automatically recognisable WCAG breaches, and names per finding the success criterion and a concrete step. It finds roughly 20–35% of issues and does not replace a full assessment.

Read on

• Images of text per WCAG 1.4.5
• Link text per WCAG 2.4.4
• The four WCAG principles

General information to the best of our knowledge, not legal advice. For an individual case, contact a law firm specialising in IT law.