List every image on a page with its alt text, and flag images with missing, empty or weak descriptions.
How to use the Image alt checker
- Enter a URL.
- Review the flagged images.
- Write short alt text that says what each meaningful image shows.
Good alt text
Describe what the image shows and why it is there, in a short phrase. Decorative images should have empty alt (alt="") so screen readers skip them. Don't stuff keywords.
What each label means
Missing: the img tag has no alt attribute at all. Screen readers may read the file name aloud, and it is always worth fixing. Decorative: alt="" is set on purpose, which is correct for dividers, background shapes and icons next to text, but wrong for a product screenshot. Weak: the alt text is a placeholder like "image", "logo", "photo1" or a file name such as hero.png, which tells nobody anything. OK: there is real text; read it to make sure it describes the image. Tick "Only show problems" to focus on what needs work. Up to 300 images are listed.
Writing alt text that helps
For a screenshot, say what it shows: "Invoice editor with a line item and a due date". For a logo, use the company name. For a chart, give the takeaway, not the colours. Keep it under about 125 characters, skip "image of", and don't repeat a caption that sits right under the image. If a CMS auto-fills alt with file names, turn that off and fix the existing images in bulk.