Why alt text matters
Alt text is read aloud by screen readers, shown when an image doesn't load, and used by search engines to understand images. Decorative images should have an empty alt="" so screen readers skip them; informative images need a short description.
What is flagged
- No alt attribute at all.
- alt="" (fine for decorative images, listed so you can check).
- Alt text longer than 125 characters, repeated alt text, and alt text that is just the file name.
- Generic file names (IMG_1234.jpg, DSC00001.jpg, screenshot.png). Renaming files is a small bonus for image search, not a ranking guarantee.
Frequently asked questions
Should I put keywords in alt text?
Describe the image accurately. If the image shows your topic, the words will come naturally; stuffing keywords makes alt text useless for screen reader users.
Are background images checked?
No. CSS background images aren't in the HTML as <img> elements, so they can't have alt text. Use <img> for images that carry meaning.