Alt text is a text-based representation of non-text content that is read by screen-reader software so that people with visual or cognitive disabilities can access and understand the non-text content. Alt text for an image presents the content and function of the image, not a description.
Content – consider the surrounding context of the image to evaluate its purpose
Function – consider if the image performs a function
Description – a label or detailed caption of the visual
Meaningful Images – these images portray significance within the surrounding context
Purely Decorative Images – these images are insignificant, do not add meaning, and do not require alt text
Assure all meaningful images are equipped with alt text that conveys the content and functionality of the image.
Context: the following imagery is found in an electronic pamphlet for a doggy daycare
|Bad Alt Text: beagle dog||Good Alt Text: beagle dog playing fetch in an open field|
Think carefully about whether an image adds meaning to your content
Be succinct and specific when adding alt text to an image
Don’t start alt text with “Image of…”
When your alt text is longer than a sentence in length you may want to consider eliminating the image and using text-only content
Alt text is used for images as well as other non-text content such as graphs, tables, infographics, etc.
- Alternative Text Options in Microsoft Word (PDF: 145 Kb)
- Teaching Center Alternative Text Guidelines
- WebAIM Alternative Text (opens in a new tab)
- WebAIM Alternative Text Blunders (opens in a new tab)
What can you do right now?
Consider performing an audit of your existing electronic content and media to see if and how you can add alt text to enhance the accessibility of your content.
Download free screen reader software to hear how alt text is accessed by a screen reader user to put yourself in their shoes.