WCAG (Web Content Accessibility Guidelines) 2.2 is the standard most accessibility laws point at: the ADA in the U.S., Section 508 for federal contractors, AODA in Ontario, EAA in the EU. When an auditor checks your site for alt text compliance, they're checking against WCAG Success Criterion 1.1.1: every non-text element must have a text alternative that conveys equivalent meaning.

This guide explains what 1.1.1 actually requires, what auditors look for, and how to bring a noncompliant site into compliance without rewriting every page from scratch.

Key Takeaways

• WCAG 2.2 SC 1.1.1 (Level A) requires alt text on every non-decorative image, sufficient to convey the same information.
• Decorative images need empty alt (alt="") — not missing alt.
• Form image-buttons, image-links, and CAPTCHA images have specific 1.1.1 requirements that auditors flag fast.
• Most U.S. ADA web lawsuits cite WCAG 2.1 or 2.2 AA as the standard. That includes 1.1.1.
• Automated audits catch missing alt text reliably; only manual review catches inadequate alt text.

What WCAG SC 1.1.1 Requires

The full text of Success Criterion 1.1.1: Non-text Content says all non-text content presented to the user must have a text alternative that serves the equivalent purpose. "Equivalent purpose" is the load-bearing phrase. Saying "image" in the alt text is not equivalent. Saying "Bowl of cacio e pepe pasta with cracked black pepper" is.

The criterion has six sub-categories that each get specific treatment:

1. Controls and inputs

Image buttons (<input type="image">) and image links need alt text describing the function, not the visual. "Submit" is right; "Green button" is wrong.

2. Time-based media (audio/video)

Out of scope for this guide; handled by SC 1.2.x. Alt text on a video poster image is still required.

3. Test or exercise content

If the alt text would give away the answer, you can use a placeholder description that doesn't compromise the test.

4. Sensory experience

Art, music visualizations, mood photography. Provide a brief description even if a full equivalent isn't possible.

5. CAPTCHA

Provide alt text identifying the purpose plus an alternative form (audio CAPTCHA, etc.).

6. Decoration, formatting, invisible

Set alt="". The screen reader will skip it cleanly. Missing alt does not satisfy 1.1.1.

Conformance Levels: A, AA, AAA

WCAG criteria are tiered. SC 1.1.1 is Level A, the lowest bar, meaning a site at any conformance level must satisfy it. Most accessibility laws and contracts require AA conformance, which includes A. AAA is aspirational. For alt text, the level distinction doesn't matter much: 1.1.1 is foundational and you can't skip it.

ADA Enforcement in the U.S.

The Americans with Disabilities Act doesn't name WCAG explicitly, but federal courts have repeatedly accepted WCAG 2.0/2.1 AA as the de facto compliance standard. The DOJ's 2024 final rule on Title II web accessibility requires public entities to meet WCAG 2.1 AA, and private companies subject to Title III follow the same precedent.

Plaintiffs' law firms file thousands of ADA web lawsuits per year, with missing alt text consistently cited as a high-volume violation in industry trackers like UsableNet's annual report. Settlements aren't public, but disclosed amounts and law-firm marketing materials suggest typical resolutions land in the low-to-mid five figures plus legal fees and remediation costs. Missing alt text is one of the easiest violations to detect proactively, and fix before a complaint hits.

For deeper ADA coverage including the 2024 DOJ rule, see ADA Compliance for Images (2026 Guide).

Section 508 (Federal Contractors)

Section 508 of the Rehabilitation Act applies to U.S. federal agencies and contractors. The 508 standards explicitly reference WCAG 2.0 Level AA, and any government website procurement requires it. SC 1.1.1 is in scope. For specifics, see Section 508 Alt Text Requirements.

Other Jurisdictions

• EU — European Accessibility Act (EAA): applies to most consumer-facing digital products from June 2025. References EN 301 549, which incorporates WCAG 2.1 AA.
• Canada — AODA: Ontario's accessibility law requires WCAG 2.0 AA for public-facing sites since 2021.
• UK: public-sector bodies require WCAG 2.2 AA under the Public Sector Bodies Accessibility Regulations.

If you operate internationally, WCAG 2.2 AA (which 1.1.1 falls under) is the broadest umbrella to comply with.

What an Accessibility Audit Actually Checks

Audits run in two layers: automated and manual. Automated tools (axe, WAVE, Lighthouse, AccessiBe scanners, internal CI checks) catch missing alt attributes on every page. Manual review catches the harder problems: alt text that exists but is wrong, decorative images marked as informative, and informative images marked decorative.

Audit output typically includes:

1. Missing alt — count of <img> elements without an alt attribute.
2. Empty alt that should be descriptive — manual reviewer flags these.
3. Filename-as-alt — alt text that's just the filename ("DSC_0421.jpg").
4. Generic alt — "image", "photo", "graphic", "logo".
5. Redundant alt — image alt text that duplicates the adjacent caption.
6. Stuffed alt — alt text obviously written for keyword cramming.

You can run a free audit yourself to see how your site stacks up. AltText.ai's crawl analyzer scans up to 25 pages for missing alt text and shows the findings inline.

Bringing a Noncompliant Site Into Compliance

Three-step remediation playbook:

Step 1: Audit the gap

Run an automated scan to count missing alts. Most sites discover that 30–80% of images lack alt text once they look. The free accessibility crawl gives you the count for the first 25 pages of your domain in about 60 seconds.

Step 2: Triage decorative vs informative

For each missing alt: decide whether the image is decorative (set alt="") or informative (write a real description). The decorative images guide covers the distinction in detail.

Step 3: Generate descriptions at scale

For sites with hundreds or thousands of informative images, manual writing is the bottleneck. Automated alt text generation, using AI to produce context-aware descriptions and having a human review, is the standard playbook. AltText.ai is one option; web.dev's accessibility track covers the manual approach. Either way, the goal is consistent quality across the catalog, not perfection on each individual image.

Common 1.1.1 Violations and Their Fixes

• Missing alt entirely: add the attribute, even if empty (alt="" for decorative).
• Filename as alt: rewrite descriptively. "Golden retriever returning a tennis ball" beats "DSC_0421.jpg".
• Generic alt ("image"): describe the actual subject and context.
• Image button with no purpose: describe the action (alt="Submit") not the visual (alt="Green button").
• Linked logo with descriptive alt: describe the destination (alt="AltText.ai home") not the visual.

Next Steps

Run a free site-wide accessibility crawl to find every missing alt on your site. Then use AltText.ai to generate compliant descriptions at scale — pricing starts free with 25 images. For deeper coverage:

• What Is Alt Text? (Complete Guide)
• ADA Compliance for Images (2026)
• Screen Reader Alt Text
• Empty Alt Text: When to Use It
• Decorative Images and Alt Text
• Section 508 Alt Text Requirements