WCAG Alt Text Requirements: A Technical Guide for Website Owners

Learn WCAG 1.1.1 alt text requirements, common failures, and how to prioritize fixes—technical guidance only, not legal advice.

BLUF

WCAG 2.1 Success Criterion 1.1.1 requires a text alternative for non-decorative images. This is a technical accessibility pattern—not a guarantee of legal compliance.

What counts as non-text content

Informative images, icons with meaning, charts, and functional controls need alt text that conveys purpose. Purely decorative images should use empty alt (alt="") so screen readers skip them.

Common failure patterns

Missing alt attributes
Filename placeholders (IMG_2043.jpg)
Keyword stuffing or vague text like "image" or "photo"

How to prioritize fixes

Start with templates (header, footer, product cards), then high-traffic landing pages. A free alt text scan helps you see volume before you edit CMS fields.

Authoritative references

Frequently Asked Questions

Is alt text required for every image? Decorative images should use empty alt; informative images need meaningful alternatives.

Does WCAG equal ADA compliance? No. WCAG is a technical standard; legal outcomes depend on many factors outside a scanner.

Can AI write my alt text? AI can suggest drafts; a human should review before publish.

How do I test quickly? Use a technical crawler that lists missing or weak alt patterns across multiple pages.

Check your site's alt tags →