Figure Alt Text
Figure alt text provides an accessible text alternative for visual information. Simple informative figures may need a concise description; complex charts and diagrams usually need a short identifier plus a fuller accessible description or data equivalent.
Write alt text around the figure’s purpose and essential information. For complex figures, pair a short text alternative with a fuller description or equivalent data rather than trying to compress everything into one short alt attribute.
Key details
Important caveats
Duplication Boundary
Coordinate alt text with nearby captions and body text so screen-reader users do not hear the same information repeated unnecessarily.
Further guidance
Complex Images
For complex figures such as charts or diagrams, use a short identifying text alternative plus a fuller description or equivalent data when the information cannot fit meaningfully in short alt text alone.
Informative Images
For informative figures, write alt text that conveys the essential information or function rather than merely naming the file or saying “image.”
Practical Application
Write alt text for the figure’s purpose and essential information in context. For a complex chart, diagram, or figure whose important information cannot be conveyed briefly, use a concise alternative that identifies the key purpose and provide a fuller description or equivalent data nearby or through an appropriate long-description mechanism.
Reader Check
Would a reader who cannot see the figure receive the information or function needed from it without hearing redundant caption text or a useless filename description?
Worked Example
For a line chart whose main point is that complaints fell from January to June, use brief alt text that states that trend and provide the underlying values in nearby text or a data table if those values are necessary to the content.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Alt text, captions and titles for images (opens in a new tab)Australian Government Style Manual · Distinct purposes of image/figure titles, captions and alt text; figure numbering in long-form content; caption/alt accessibility boundaries
- Complex Images — W3C WAI Images Tutorial (opens in a new tab)W3C Web Accessibility Initiative · Accessible text alternatives for complex images such as graphs and charts, including short identification plus fuller description