Alternative text for images

The content contained in images, including pictures, illustrations, and charts, is inaccessible to people who can't see those images. Alternative text is added to images to describe the content of the images for screen readers.

What is important to include in alternative text?

Alt text should convey the purpose of an image so that if someone can't see the image they can still obtain the important information the image conveys. Alt texts aren't an exact science, but several accessibility sites have suggestions to help you decide what to include in your alternative text.

• W3C discussion of alt texts
• WebAIM's discussion of "Alternative Text Basics"

How to verify

The simplest way to verify is to browse your site on staging with a browser that has the WAVE Toolbar installed. Running the "Errors, Features, and Alerts" report will show you where problems exist.

If you cannot install the WAVE Toolbar in your browser, try using the WAVE online web accessibility checker tool instead.