How to Write Alt Text for Ebook Images

Start with purpose, not appearance

Ask why the image is present. A headshot used to identify an author needs different alternative text from a chart that carries quantitative information or a decorative flourish that carries no content.

Do not repeat nearby text unnecessarily

If a caption or paragraph already communicates the important information, the text alternative should complement that context rather than make screen-reader users hear the same content twice.

Complex images need more than one sentence

Charts, maps, diagrams, and instructional illustrations may require a concise alt attribute plus a longer description in the surrounding content. The goal is equivalent access to the information, not a word-count target.

Keep authors involved

The author or subject expert should approve descriptions when interpretation matters. A production specialist can improve structure and wording, but should not guess at the meaning of specialized visual content.