Alt text checker

Audit every image on a page: missing alt attributes, file names posing as descriptions, empty alt on links, keyword stuffing and image SEO basics.

Checked in your browser. Page HTML fetched for a URL check is not stored.

How to read the results

Fix means a WCAG 1.1.1 (Non-text Content) problem that is almost certainly real: no alt at all, a linked image with no text, or alt that is a file name. Review means a human should look: very long alt, an "image of" opener, a one-word alt. OK means no automated rule fired, which is not the same as good.

What a checker cannot tell you

Whether "Chart" is enough for a chart (it is not), whether a photo is really decorative, or whether the alt says what the image means on this page. Those calls need the alt decision tree.

Rules used

  • Missing alt on <img>, <area> and <input type="image"> fails WCAG 1.1.1 and, for linked images, 2.4.4 Link Purpose.
  • Inline SVGs need role="img" with aria-label or a <title>, unless aria-hidden="true".
  • role="presentation" and aria-hidden="true" images are treated as decorative.

Sources: Understanding WCAG 2.2 SC 1.1.1; W3C WAI Functional Images.

Common failures, quick fixes

<img src="logo.svg"> in a home linkalt="Acme home"
alt="IMG_4031.jpg"Describe it, or alt="" if decorative
alt="Image of our team"alt="Our five-person support team in the Leeds office"
Keyword list in altOne honest phrase; keyword once if true

Questions people ask

What does the alt text checker look for?

Every <img>, image input, <area> and inline SVG on the page. It flags missing alt attributes, empty alt on linked images, file names or camera names used as alt, "image of" openers, keyword repetition, very long alt, and missing width/height or lazy loading for image SEO.

Is an empty alt attribute an error?

Not always. alt="" is the correct way to mark a decorative image so screen readers skip it. It is an error when the image is the only content of a link or button, because then the control has no name. The checker distinguishes the two.

Can an automated checker prove alt text is good?

No. It can find missing and obviously broken alt text, but only a person can judge whether the alt conveys what the image means in context. Use the results as a to-do list, then review with the W3C WAI alt decision tree.

Why did the URL check fail?

Some sites block automated requests, need a login, or build their page with JavaScript after load. In those cases open the page, view its source (or copy the rendered HTML from your browser's developer tools) and paste it into the HTML box.