methodology / Accessibility / #56

Color contrast (WCAG AA)

live factor #56 · Accessibility · scoring impl: implemented · weight 1.3%

What we measure

Text needs sufficient contrast against its background to be readable for low-vision users. WCAG AA requires 4.5:1 for normal text and 3:1 for large text.

How to improve your score

Adjust foreground or background colors until you hit the ratio. Online tools like WebAIM's Contrast Checker make this trivial.

Data source

Data source for this factor is not yet documented.

Implementation notes

Pull contrast violations from Lighthouse a11y audits, list affected selectors.

Scoring

Scoring formulas are versioned with the methodology. The current method (v1.1.0) maps raw measurements to pass, warn, fail. Factor weights determine how much each contributes to the composite — see the methodology index for the full table.

Version history

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