Free alt text checker

1. 1

   No alt attribute (fix)

   An image with no alt at all gives Google no text for it, and some screen readers read out the file name instead (W3C, decorative images). An image named with aria-label or title, or hidden from screen readers, gets a note instead.

2. 2

   Linked image with no name (fix)

   When an image is the only thing in a link or button, its alt text is the link's name. It should say where the link goes, like “Example.com homepage” rather than “Example.com logo” (W3C, functional images).

3. 3

   File name as alt text (fix)

   IMG_4821.jpg, hero_banner or blue-shoes-01 describe nothing. WebAIM counts file names as questionable alt text.

4. 4

   Says nothing (check)

   Alt text that is only "image", "photo", "logo", "blank" or "placeholder". Say what the image shows, or whose logo it is.

5. 5

   Keyword stuffing (check)

   The same word 3 or more times in one alt text, making up a fifth of its words, in a list rather than a sentence (plurals count together). Google's image guide shows a stuffed example and says it can make a site look like spam.

6. 6

   Starts with "image of" (note)

   Screen readers already announce an image, so "image of", "picture of" and "photo of" are wasted words. "Screenshot" or "illustration" is fine when the kind of image matters.

7. 7

   Over 125 characters (note)

   No standard sets a limit. It's a prompt to cut: the W3C asks for the shortest description that does the job.

8. 8

   Empty and repeated alt text (note)

   alt="" tells screen readers to skip an image, which is right for decoration. The checker lists them so you can confirm none of them carries meaning, and notes different images that share the same alt text.

Bad (missing alt text)

<img src="puppy.jpg"/>

Bad (keyword stuffing)

<img src="puppy.jpg" alt="puppy dog baby dog pup pups puppies doggies pups litter puppies dog retriever labrador wolfhound setter pointer puppy jack russell terrier puppies dog food cheap dogfood puppy food"/>

Better

<img src="puppy.jpg" alt="puppy"/>

Best

<img src="puppy.jpg" alt="Dalmatian puppy playing fetch"/>

“Better” names the subject. “Best” says what this picture shows that another puppy photo wouldn't. The stuffed version repeats “puppy” and “dog” and lists words the photo doesn't show; paste it into the checker and it is flagged.

• Google uses alt text along with computer vision and the contents of the page to understand what an image shows. It asks for “useful, information-rich content that uses keywords appropriately and is in context of the content of the page”, and warns that filling alt attributes with keywords “may cause your site to be seen as spam” (Image SEO best practices, updated March 2, 2026).
• The same guide says alt text is useful as anchor text when an image is a link, and that Google doesn't index CSS background images.
• WebAIM says alt text shouldn't start with “image of” or “graphic of”, because screen readers already announce it as a graphic, and that when an image is the only content of a link or button, empty alt text is never right (Alternative text).
• The W3C asks for “the most concise description possible of the image's purpose”, with the most important information first (Tips and tricks). Decorative images get alt=""; leaving alt out is not an option, because some screen readers then read the file name (Decorative images).
• On the top million home pages in February 2026, 16.2% of images had no alt text, 45% of those were linked images, and 10.8% of images with alt text had questionable or repeated alt text such as “image”, “graphic”, “blank” or a file name. Missing alt text was found on 53.1% of home pages (WebAIM Million 2026).

A live page

Open the page, view its source (Ctrl+U on Windows, Cmd+Option+U in Chrome on a Mac), select all and copy. Images that the page adds with JavaScript aren't in the source: in the browser's developer tools, right-click the <html> element and copy its outer HTML instead.

An editor or another page

Select the content and copy it. Each image comes through as an <img> line with the alt text the copy carried. Editors don't always include alt text when you copy, so if every image shows as missing, check the published page's source.

Markdown

Images written as , and any <img> tags in the draft. Images inside ``` code blocks or `code` are skipped. In Markdown,  publishes as alt="", so it shows as empty.

The checker doesn't fetch pages or load images, so it works on drafts and on pages behind a login. It can't see an image, so it can't tell whether the alt text matches what's in it. Read the list with the page open.

• Cover and section images get alt text written from what they show, in plain words and under 125 characters, without “photo of” at the start and without repeating the keyword.
• You can edit any image's alt text before the article goes out.
• The cover's alt text is sent to WordPress, Ghost, Webflow and Shopify along with the image.

3 days free, no card.