The images below demonstrate three different approaches to alt text tagging. Again, noting that the text you are seeing (or not) when you mouse over the images, is showing the title of the image, not the alt text. For this demonstration we are showing the best practice of how to best describe the image.
- Review WebAIM’s article on Alternative Text for a comprehensive set of guidelines to using alt text on web pages.
- These alt text blunders from WebAIM provide examples of practices to avoid when creating alt text.
- Effective Practices for Description of Science Content within Digital Talking Books, published by the National Center for Accessible Media (NCAM), provides guidelines for writing alt text descriptions for complex images, such as graphs and charts.
- For a quick overview on how to create a text-based version of a complex image, like a line graph or timeline, download the NCAM brochure, Describing Science Images for Learners with Disabilities.
- The Image Description Guidelines, published by the DIAGRAM Center, contain detailed guidelines for describing, summarizing, and converting a variety of image types, in order to improve their accessibility.