Adding Alt Text for Simple Images
Why Add Alt Text?
Alt text (alternative text) provides a description of images for students who use screen readers or those who have visual impairments. It ensures that all learners can understand the content, even if they can’t see the image. Alt text is also helpful if an image fails to load, giving context to users about what the image represents.
What Makes Good Alt Text?
- Concise and Informative: Alt text should briefly describe the content or function of the image.
- Avoid Redundancy: Don’t repeat information already provided in the surrounding text.
- Focus on Purpose: Think about why the image is included and what information is essential for the student to understand.
How to Create Effective Alt Text
Describe the Image’s Content
- Describe what is in the image and focus on its essential elements.
- Example: For an image of a bar chart showing student grades, use “Bar chart depicting average student grades by subject.”
Keep It Brief
- Alt text should be clear and succinct. This ensures that screen reader users get quick, useful descriptions.
- Example: Instead of “This is an image of a bar chart that shows the different grades students received in various subjects over the past semester,” simply use “Bar chart of student grades by subject.”
Avoid “Image of” or “Picture of”
- Screen readers already identify the content as an image, so there’s no need to add “image of” or “picture of.” Go straight to describing the key content.
- Example: Instead of “Image of a graduation cap,” use “Graduation cap representing student success.”
Examples of Good vs. Bad Alt Text
Example 1
- Bad: “Image of a cat.”
- Good: “Orange tabby cat sleeping on a windowsill.”
Example 2
- Bad: “Picture of students.”
- Good: “Three students studying together in the library.”
Tips for Faculty
- Decorative Images: If an image is purely decorative and doesn’t convey information relevant to the content, mark it as decorative. This way, screen readers will skip it, reducing noise for people.
- Context Matters: Describe the image in a way that adds value. Think about what you want students to learn or understand from the image.
What Can I Do Now?
Take immediate steps to enhance the accessibility of your content. Start by reviewing all images in your course materials, including lecture slides, assignments, readings, and any embedded multimedia content, to ensure they have meaningful alt text. Alt text should help students using screen readers understand the visual elements by being concise and conveying the essential purpose of each image without repeating information already presented in the surrounding text. For purely decorative images, mark them accordingly so they do not distract learners. When reviewing your course materials, use accessibility checkers, like the Canvas built-in tool, Microsoft Accessibility Checker, Google Accessibility Checker, Adobe Acrobat’s Accessibility tool, or third-party tools such as WAVE or Axe, to verify that all images have appropriate alt text and to identify any issues. By integrating these practices now, you can create a more inclusive learning environment where every student has equal access to the course content.