Make Images and Diagrams Accessible 

Images, charts, graphs, and diagrams are commonly used in course materials to illustrate concepts or present information. To ensure all students can access this information, visual content should include descriptions that communicate the meaning or purpose of the image.

Students who use screen readers cannot see images, so alternative text (alt text) allows assistive technology to describe the visual content. Providing clear descriptions also benefits students reviewing materials on small screens or in low-bandwidth environments.

Provide Alt Text for Images 

Images included in course materials should include alt text that describes the purpose or meaning of the image.

Alt text should:

• Briefly describe the important information conveyed by the image

• Reflect how the image relates to the course content

• Focus on the meaning of the image rather than every visual detail

Describe Important Visual Information 

If images, charts, or diagrams convey important information, ensure that the key ideas are also explained in the surrounding text or during lectures.

For example:

• Describe trends shown in graphs or charts

• Explain key elements of diagrams

• Summarize visual information presented in figures

Providing descriptions ensures that all students receive the same information presented visually.

Avoid Using Images of Text 

Whenever possible, avoid using images that contain large amounts of text.

Text embedded within images can be difficult for assistive technologies to interpret and may be difficult for students to read or resize.

Instead, provide the information as regular text within the document or Canvas page.

Resources for Writing Alt Text 

These resources provide guidance on writing effective alternative text and describing complex images:

• WebAIM: Alternative Text 

• W3C Alt Text Decision Tree 

• ABLETech Describing Complex Images Course