An ARIA label is an attribute that supplies an accessible name for an interface element, giving a screen reader concise text to read aloud. It is especially useful for chart elements and other objects that need labels beyond an image’s alt text. section 7.3.4
Use an ARIA label thoughtfully:
- Choose aria-label when the needed text is not already visible elsewhere on the screen. section 7.3.4
- Use the companion referenced-label attribute when visible text already exists elsewhere and can be linked through an element ID. section 7.3.4
- Keep labels short and specific—about three words at most—rather than turning them into miniature essays. section 7.3.4
- Generate labels dynamically when the visualization’s content changes, so screen-reader users receive labels for the current state. section 7.3.4
- If the tool cannot add an ARIA label, provide meaningful descriptive text or a caption instead of leaving the visual unexplained. section 7.3.4
Labeling a bar chart
Give each bar its own concise ARIA label, such as a category and value. When the same wording is already displayed elsewhere in the visualization, reference that existing text rather than duplicating it. section 7.3.4
