The same office photo may be decorative on the home page but evidence of the project environment in a case study. Alt text cannot be fixed from the image file alone; it depends on what information the image carries in the current context.
Both extremes are common: every image uses alt="image", or every image repeats a long keyword list. The first provides no help; the second creates noise.
01 Ask What Information Disappears Without the Image
If nothing is lost, the image may be decorative and should use empty alt text so screen readers skip it.
If the image communicates a product, action, evidence, or data, alt text should provide equivalent information needed for the current task.
Alt Text for Different Image Types
| Image Type | Recommendation | Example Direction |
|---|---|---|
| Product image | Name plus an important visible feature | Front and connectors of a sensor model |
| Case-study screenshot | Describe the interface or change | Order-management filters and bulk actions |
| Logo | Brand name, according to link destination | JVDS home page |
| Linked or button image | Describe the action or destination | Download the annual report |
| Decorative background | Use empty alt | Do not repeat nearby copy |
| Chart | Short conclusion plus detailed nearby data | Trend summary; table provides exact values |
| Infographic | Summarize purpose and provide a text equivalent | List every step in the body |
02 Do Not Repeat Nearby Copy
If the heading already says “Corporate Website Design Process,” alt text need not repeat it word for word. Describe only information unique to the image.
A screen reader announces items in sequence, so repetition adds burden.
03 Give Complex Images a Long-Form Text Alternative
A flowchart, data visualization, or architecture diagram cannot be fully explained in one alt attribute. Use alt for the summary and provide structure and data in the body or an expandable description.
Do not place an entire explanation in the alt attribute; it becomes difficult to read and maintain.
04 Accurate Context Is Still the Basis of Image SEO
Filename, heading, surrounding copy, image quality, and page topic all help interpretation. Alt text can include a relevant term naturally but should never become a keyword list.
When the same stock image appears on several pages, do not copy one meaningless generic alt value automatically.
05 Let Editors Write Alt Text for the Context
Provide an alt field and short guidance, and allow decorative images to be left explicitly empty. Automated generation can suggest text but needs human review.
During migration, identify missing, duplicated, filename-style, and excessively long alt text.
06 Include Images in Keyboard and Screen-Reader Testing
Check names for linked images, icon buttons, carousels, lazy loading, and error placeholders.
Alt text is only one part of accessibility; color, captions, text alternatives, and interaction also matter.
Frequently Asked Questions
Can decorative images omit alt text?
Keep alt="" to tell assistive technology explicitly to skip the image rather than omitting the attribute.
How long should alt text be?
There is no absolute character count. Express the purpose concisely and put complex information in the body.
Can a logo use “company logo” as alt text?
The brand name is more useful. If the logo links to home, describe the destination clearly.
Can the image title attribute replace alt?
No. Title behavior is inconsistent; alt provides the image alternative.
Can AI-generated alt text be published directly?
It can assist, but may miss page context. Review it, especially for products and charts.
| Service | View |
|---|---|
| Related service | View service details |
| Project inquiry | Contact JVDS |
| Design and website articles | View all articles |
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