SEO & Accessibility

Image alt text checker

Scan a public page for images with missing or blank alt attributes.

Checks up to 200 <img> tags on the page HTML.
Enter the correct answer.
Today’s tool allowance
  • Domains: 3 left of 3
  • Unique URLs: 10 left of 10
  • Runs: 10 left of 10

Create a free account or see plans for higher limits.

Image alt text checker for SEO and accessibility

Every meaningful photo, product shot, and diagram on a page should have clear alternative text. Missing or empty alt attributes hurt screen-reader users, weaken WCAG 1.1.1 compliance, and give search engines less context about what your images show. This free checker fetches one public URL, scans the HTML for <img> tags, and lists images with a missing alt attribute or blank/whitespace-only alt value—plus a compact tag snippet so you can find the exact markup in your theme or CMS.

Why image alt text still matters

Alt text is the primary way assistive technology describes images. It also helps when images fail to load and supports image search and topical relevance. Thin or keyword-stuffed alt rarely helps rankings; accurate, concise descriptions do. Running a dedicated alt pass before a launch or redesign is faster than hunting issues only inside a full accessibility report.

What this tool flags

  • Missing alt — the attribute is absent (usually critical unless the image is marked decorative)
  • Blank alt — alt="" or spaces only (acceptable for decorative images; review everything else)
  • OK — a non-empty alt string is present
  • Tag hint — a truncated <img src="…" class="…" …> snippet plus CSS-like location

Images marked with role="presentation", role="none", or aria-hidden="true" are treated as decorative so intentional blank alt does not crush your score. Prefer writing alt="" explicitly instead of omitting the attribute on decorative graphics.

How to write better alt text

  • Describe the purpose of the image in context—not every pixel
  • Keep it short; long essays belong in nearby captions or body copy
  • Skip “image of” / “picture of” prefixes when they add nothing
  • Do not dump keyword lists into alt; stuffy alt looks spammy and reads poorly
  • Match language to the page (same locale as visible content)
  • Re-check after media library imports, theme updates, and page builders that inject new images

When to use this checker

  • Pre-launch QA for landing pages and ecommerce product galleries
  • Cleanup after a CMS migration that dropped attributes
  • Agency handoffs where clients need a simple alt punch-list
  • Quick spot checks between deeper accessibility or SEO audit runs

Limits and scope

The scan covers HTML <img> tags on the submitted page (up to the tool’s image limit). It does not crawl the whole site, and it does not evaluate CSS background images, SVG icons without <img>, or canvas drawings. Lazy-loaded sources from common data-src / srcset attributes are included when present in the markup.

Frequently asked questions

Is blank alt always bad?

No. Decorative spacers and redundant icons often should use alt="". Blank alt on product photos, charts, or informative screenshots usually needs a real description.

Does this crawl every URL on my domain?

No. Submit each important template or page you care about. For broader site health on paid plans, see Site Report.

Can I automate this check?

Pro plans with API access can call the same logic via the Tool API (image_alt).

How is this different from Accessibility Checker?

Accessibility Checker covers many WCAG-oriented rules. This tool focuses only on missing and blank image alt so you can clear image debt quickly and see the exact <img> tag to fix.