- Success Criterion 1.1.1
- Conformance level A
Chart Drawn in Canvas With No Fallback Description
1.1.1 — Non-text Content
Scenario
Setting
A hospital's patient portal appointment scheduler
What’s wrong
<canvas> charts/drawings with no fallback content or text alternative.
Example
Watch a hospital's patient portal appointment scheduler closely and you'll spot this: <canvas> charts/drawings with no fallback content or text alternative.
Why it matters
Blind and low-vision people using screen readers, and anyone who browses with images disabled, when icons or photos carry meaning. Here, on a hospital's patient portal appointment scheduler, the result is they miss information that's only conveyed visually.
How to test
Inspect the canvas element's children in DevTools: canvas has no built-in accessibility, so it needs fallback content or an adjacent accessible summary — if absent, it fails.
How to fix
Provide fallback content inside <canvas> or an adjacent text/table equivalent of the drawing.
Outcome
After the fix, the same visitor to a hospital's patient portal appointment scheduler can now get the same information as everyone else.
Who is affected
Blind and low-vision people using screen readers, and anyone who browses with images disabled, when icons or photos carry meaning.
Learn more
- Understanding Understanding document (opens in a new tab)
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