Alternative Text (Alt-Text)

All images must have alternative text that describes them except for decorative images which should be marked as decorative. The purpose of alt text is to provide a text equivalent of the image, so people who are unable to see the image have access to the message it’s intended to convey. Screen readers and other machines (such as search engines) can't read images and rely on text alternatives and transcriptions. Supplying concise and equivalent alt text ensures equitable course content for all students and all types of devices.

Best Practices for Writing Alternative Text

  • Be descriptive. Describe the image content clearly and concisely.
  • Keep it short. Aim for 125 characters.
  • Avoid redundancy. Don't repeat information already in the surrounding text.
  • Context matters. Tailor the alt text to the context in which the image is used.

Common Mistakes to Avoid

  • Vague Descriptions
  • Ignoring decorative images
  • Saying "image of"

Helpful Alt-Text Resources

YuJa Panorama

Within eLearn, Panorama will flag items without an alternative description as having a severe accessibility issue. When in Edit Page mode, you can click Fix Issue within the Panorama Accessibility Report and Panorama will suggest alternative text for the image. *Yuja Panorama uses AI to generate their alternative text. It is imperative you check the AI suggested alt-text for accuracy. 

Image Accessibility Creator

Writing alt-text for complex images and infographics can be challenging.

Arizona State University has an Image Accessibility Creator which can be helpful when writing complex alt-text.​​​​​​​

  1. Upload an image to the Image Accessibility Creator.
  2. Click Create Image Details.
  3. Once the image has been analyzed, an Image Breakdown will be provided. You will receive a long description and an abbreviated alt-text description. Review both for accuracy and before determining what alt-text you add to your image. 

Assessments and Alt-Text: Balancing between Accessibility and Giving the Answers

Images are likely to have different alt-text descriptions depending on if the image is used within teaching material or within an assessment as testing material.

The image used within teaching material needs to have a full description. While the image within testing material needs to provide enough context for the learner to know what image you are asking about but not provide the answers. They are meant to be recalling the answers you provided in the full alt text in the teaching resource.

An example using a cell membrane image is listed below.

A cell membrane consists of three layers. From outside to inside they are the cell exterior, a phospholipid bilayer, and the cell interior.

 

For Instruction:

Alt text - A cell membrane consists of three layers. From outside to inside they are the cell exterior, a phospholipid bilayer, and the cell interior.

For Testing:

Alt text - A cell membrane consists of three layers.

Sample question - Identify the middle layer of a cell membrane.

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