canvas-text-alternative-present

<canvas> must provide a text alternative

Checks that <canvas> elements provide a text alternative via fallback content or an accessible name.

Applies to. Applies to <canvas> elements included in the accessibility tree. Hidden elements are excluded whether or not they are focusable.

Expectation. Each applicable <canvas> provides a text alternative via fallback content or an accessible name, with two exceptions:

• role="img" (the first token of the role attribute that names a known role, matched case-insensitively) makes the canvas's children presentational and its name comes from the author only, so fallback content does not count: aria-labelledby, aria-label or title must name it.
• role="none"/"presentation" (resolved the same way) marks the canvas decorative, and it passes. The role is ignored (presentational role conflict) when the canvas is focusable or carries aria-label/aria-labelledby, and the canvas is then judged like any other.

Examples

<canvas>Chart summary</canvas>

<canvas></canvas>

Related rules

• canvas-text-alternative-quality

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