W3C WCAG 1.4.3 Contrast (Minimum) (Level AA)
Ensure text and images of text have at least 4.5:1 contrast ratio against backgrounds, with 3:1 for large text, to support users with low vision
Where this comes from
Provision: 1.4.3 Contrast (Minimum) (Level AA)
Instrument: W3C Web Content Accessibility Guidelines (WCAG) 2.2
Citation: W3C, Web Content Accessibility Guidelines (WCAG) 2.2, Success Criterion 1.4.3 Contrast (Minimum), Level AA, W3C Recommendation 05 October 2023
Text version: WCAG 2.2
Who it applies to
It applies when all of these are true:
- Service type — any answer
- Service is likely to be accessed by children under 18
What engineering work it implies
Sample acceptance criteria Landfall generates for this obligation:
- Normal text has a contrast ratio of at least 4.5:1 against its background
- Large text (>=18pt, or >=14pt bold) has a contrast ratio of at least 3:1
- Placeholder, disabled-state, and text-over-image/gradient cases are checked in both light and dark themes
- Automated contrast checks (axe/Lighthouse/WebAIM) pass on all changed views; documented exceptions cover only logos/incidental text
- Unit tests cover the core logic (aim for >80% coverage on new code)
Questions people ask
- Does W3C WCAG 1.4.3 Contrast (Minimum) (Level AA) apply to my service?
- It applies when Service type — any answer; Service is likely to be accessed by children under 18.
- From when does this apply?
- W3C WCAG 1.4.3 Contrast (Minimum) (Level AA) applies from 5 October 2023. Its current status is: in force.
Find out whether this one lands on you
Landfall's pre-scan answers the applicability question above for your product in minutes, then turns every obligation that applies into traceable engineering tickets with a citation chain your auditors can follow.
Not legal advice. Landfall maps regulatory obligations to engineering work for planning purposes. Its verdicts are not legal advice and create no attorney-client relationship — verify with qualified counsel before relying on them.