Accessibility finding
The alternative text names something the image does not show
Accessibility Error Severity: Medium
Part of the audit Alternative text checked against the image itself. Finding id: accessibility.altContradictsImage.
What it costs you
A wrong description is worse than none: a blind visitor is told something false, and the picture can turn up in image search for the wrong thing.
What to do
Look at the image and rewrite the alt to say what it shows.
What it checks
- Description names something not shown
How to fix it
Fix
A real case
In WebAIM's 2026 scan of the top one million home pages, 10.8% of the images that had alternative text had questionable or repetitive text, and one in four linked images had none.
Thresholds
| Name | Default | Meaning |
|---|---|---|
min_confidence | 0.6 | Only count what the image model recognises with at least this confidence. |
sure_confidence | 0.9 | Above this confidence in what the image does show, the contradiction is reported as a failure and not for review. |
How to verify by hand
A person: look at the image. Image models are wrong on drawings, unusual angles and things outside their vocabulary.
What this relies on
The alt was written for another picture, or the picture was replaced and the alt was kept.