Work Through the Questions in Order
Stop at the first question that applies to your image.
-
1. Is it purely decorative?
Decorative means purely visual (a divider, texture, or border), redundant (its content is already in adjacent text), or aesthetic (a stock photo used only for visual appeal).
Yes — mark it decorative. In most tools that means leaving the alt text blank and ticking the “decorative” checkbox; in HTML it is
alt="". Screen readers will skip it entirely. Never omit the alt attribute altogether.No — continue to question 2.
-
2. Does it contain text?
Yes — transcribe the text exactly as it appears. A poster reading “Spring Symposium — April 12, 9am, Bauer Boardroom” needs that full text as its alt. Better still, put the text in the page or post body as live text as well.
No — continue to question 3.
-
3. Is it a chart or graph?
Yes — summarise the key finding or trend. For complex data visualisations, put a full data table or text description in the page body and keep the alt text brief, pointing to it: “Bar chart of enrollment by year — see table below.”
No — continue to question 4.
-
4. Describe the content and its context.
Write what the image communicates in this specific place. The same photograph needs different alt text on a news story than in a staff directory. Aim for one clear sentence.
What Counts as Decorative
Mark an image decorative when it is:
- Purely visual — a divider line, a background texture, a decorative border.
- Redundant — its content is already conveyed in adjacent text on the same page.
- Aesthetic — a stock photo used only for visual appeal, not to communicate information.
Writing Good Alt Text
| Do | Do not |
|---|---|
| Lead with what matters most | Start with “Image of…” or “Picture of…” |
| Keep it to roughly one sentence | Write a paragraph for a simple photo |
| Include text that appears in the image | Leave image text untranscribed |
| Describe the purpose in context | Reuse the same alt text everywhere |
| Name people when their identity is the point | Stuff in keywords for search ranking |
The full guide, including where to find the alt text field in each platform, is Images & Alt Text. Alt text is required for all non-decorative images under WCAG 2.1 AA Success Criterion 1.1.1.
Need Help With Something Specific?
The Help Desk can work through any accessibility task with you — one-on-one, remotely or in person.
Contact the Help Desk →