What is Long Description?
Long description is just as it sounds – a long description of an image.
When images are complex, simple alternative text is not enough. This is especially common in instructional content that students are expected to learn from, such as diagrams, charts, and graphs. In these cases, long description details everything the audience is expected to get out of the image.
Long Description Guidelines
- Long descriptions should be formatted using headings, etc., just as with other content.
- Make data tables available alongside charts and graphs. Tables provide a good alternative way of presenting the same information.
Long description is too long to put in an alt text field, so there are two options for where it should go:
- Describe the image in the surrounding text. This benefits everyone reading the material.
- If space is limited, link to an appendix where you provide the long description. Just make sure that you also link back to the original location in the text.
Connect to Alternative Text
It’s important to continue to add alt text to images even when they have a long description. The alt text should be very short and connect the image to the description somehow. For example:
- Alt Text: “Graph A”
- Long Description: “Graph A shows that…”