Writing Useful Alt Text for Website Images

Describe meaningful image information without repeating keywords.

Alt text communicates an image’s purpose when it cannot be seen. The right wording depends on whether the image demonstrates a setting, conveys data, or is purely decorative.

Describe the useful point

For a tool screenshot, explain what it demonstrates rather than listing every visual detail. Provide data in nearby text if a chart contains important information.

Handle decorative images

Decorative images can use an empty alt attribute so screen readers do not announce irrelevant details. Functional images should communicate their action.

Avoid keyword lists

Alt text is not a hidden keyword field. Review it in context and make sure important instructions are not presented only as an image of text.

Before relying on the result, test a small example, keep an original copy when a file or value is transformed, and check the output in the application where you plan to use it. Browse the tools directory for a utility that matches your task, and use the other practical guides for related checks.

Editorial note: This guide provides general educational information. Follow the requirements of the software, service, or organization involved when a task has specific rules.