This factor is part of Web Standards — the
table-stakes binary layer of the score. It is graded pass/fail and gates
the Web Quality score; it is not weighted into Web Quality itself.
Pass criteria
Tolerant — passes on pass or warn.
Web Standards label
Sufficient color contrast
Why it's required
Body text below WCAG AA contrast is unreadable to a meaningful slice of visitors. Bar passes on no critical violations.
Same factor, two depths.
What this means for your business
Pale-gray text on white is the single most-cited problem in accessibility lawsuits. It also loses customers over 50, who already squint at their phones.
Plain title: Text is dark enough to read
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.
Facts
Ticket
WEBQ-56
Category
Accessibility
Status
live
Weight
1.3%
Data source
—
Service cost
Free — Lighthouse contrast audit
Scoring impl
implemented
Method version
v1.2.0
Implementation notes
Pull contrast violations from Lighthouse a11y audits, list affected selectors.
Scoring
Scoring formulas are versioned with the methodology. The current method
(v1.2.0)
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.
Cited by these standards
Standards in the Standards Library whose satisfiedBy requirement tree references this factor. Each link goes to the standard's full entry — methodology, scope, and the other factors it relies on.
Accessibility for Ontarians with Disabilities ActAccessibilityCAIf you're a public-sector body or a private org with 50+ employees in Ontario, your website has to meet WCAG 2.0 AA — and you have to file a compliance report.
Accessible Canada ActAccessibilityCAThe federal counterpart to AODA. If you're a federally regulated entity — banks, telecoms, airlines, broadcasters — you publish accessibility plans and progress reports, and your digital surfaces are in scope.
ADA Title III (digital)AccessibilityUSCourts treat consumer-facing U.S. websites as places of public accommodation. WCAG AA conformance is the de-facto safe-harbor — the DOJ has said so since 2022.
Barrierefreie-Informationstechnik-Verordnung 2.0AccessibilityEUGermany's federal accessibility regulation. Mandates WCAG 2.1 AA (via EN 301 549) for federal public-sector websites, intranets, and mobile apps.
European Accessibility ActAccessibilityEUAs of June 2025, e-commerce, banking, transport, and digital services in the EU must meet WCAG 2.1 AA — or pay fines that escalate per member state.
Israeli Standard 5568AccessibilityOTHERIsrael's adoption of WCAG 2.0 AA, made binding for nearly every commercial website serving Israeli users by Equal Rights of Persons with Disabilities Regulations.
JIS X 8341-3:2016AccessibilityOTHERJapan's national web accessibility standard. Identical in substance to WCAG 2.0 — public-sector sites are expected to conform, private sector encouraged.
Korean Web Content Accessibility Guidelines 2.2AccessibilityOTHERSouth Korea's localization of WCAG. Public and private sites alike must conform under the Anti-Discrimination Against and Remedies for Persons with Disabilities Act.
Référentiel Général d'Amélioration de l'AccessibilitéAccessibilityEUFrance's official WCAG 2.1 AA conformance methodology. Required for public sector, and the legal compliance benchmark referenced by every French accessibility statement.
Section 508AccessibilityUSIf you sell to the U.S. federal government — or you ARE the U.S. federal government — your site has to clear this bar.
UK Equality Act 2010 (digital provisions)AccessibilityUKThe UK's ADA-equivalent. Service providers — including websites — must make "reasonable adjustments" for disabled users. WCAG AA is the de-facto evidence that you have.
WCAG 2.1 Level AAAccessibilityglobalThe version of WCAG most regulators actually wrote into law. EAA, UK PSBAR, and France's RGAA all cite 2.1 AA — even after 2.2 shipped.
WCAG 2.2 Level AAAccessibilityglobalThe web's de-facto baseline for accessibility. If a courtroom or compliance auditor asks whether your site is accessible, this is what they'll measure against.