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
Image alt text coverage
Why it's required
Screen-reader users can't navigate a site whose meaningful images have no alt text. Bar passes on ≥80% coverage.
Same factor, two depths.
What this means for your business
Blind visitors use software that reads pages out loud, and it can only describe a photo if you've written a short caption behind it. Missing alt text is the single most common item cited in accessibility lawsuits — and Google uses the same text to understand your images.
Plain title: Your photos have written descriptions
What we measure
Every meaningful image needs alt text so screen readers can describe it. Decorative-only images use `alt=""` (empty). We measure what fraction of your images have any alt attribute at all.
How to improve your score
Add `alt="..."` to every `<img>` tag. In WordPress, set it in the media library when uploading. For decorative images, use `alt=""` explicitly.
Facts
Ticket
WEBQ-54
Category
Accessibility
Status
live
Weight
1.3%
Data source
—
Service cost
Free HTML parsing
Scoring impl
implemented
Method version
v1.2.0
Implementation notes
Count `<img>` tags with vs without an `alt` attribute and report the coverage ratio.
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.
21st Century Communications and Video Accessibility ActAccessibilityUSIf your site embeds video — especially anything previously broadcast on TV — closed captions are required. CVAA also covers advanced communications services (VoIP, video chat, messaging).
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 AAccessibilityglobalThe minimum-viable baseline of the regulation-cited WCAG version. Same warning as Level A in 2.2 — failing it means basic usability is broken.
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 AAccessibilityglobalThe minimum-viable accessibility baseline. If you fail Level A, sighted-mouse users are probably also having a bad time.
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.