GEO GUIDE
Writing Alt Text: Making Images Seen
Updated 2026-10-19 · this page makes no search or citation promises
The direct answer: alt text describes the image's informational role — what it does on the page, not what it looks like. Patterns: one functional sentence, empty alt for decoration, long description for complex figures. Serves accessibility and search in one pass.
The direct answer: alt text describes the image's informational role — what it does on the page, not what it looks like. Patterns: one functional sentence, empty alt for decoration, long description for complex figures. Serves accessibility and search in one pass.
Patterns
- Functional description: a chart's alt = “2024 conversion rates by channel” — not “a colorful chart”.
- Pure decoration: alt='' (screen readers skip it) — never “image”.
- Complex figures: one-sentence conclusion in the alt; the full data in body text or a long description.
Search bonus
- Naturally include image-relevant keywords in the alt — no stuffing.
- Filenames carry semantics too: descriptive-name.jpg beats IMG_1234.jpg.
Common mistakes
- One shared alt for all images.
- Starting with “image of” — screen readers already announce it as an image.
- Alt that does not match the picture — worse than no alt for trust.