Alternative Text in Canvas

Alternative text, referred to as alt text, is a written description of an image that provides context for users unable to see it. Alt text supports students whether they have vision challenges and use a screen reader, or their device is unable to load images due to a tech issue. Instructors must evaluate if an image offers additional instructional value to the surrounding text and, if so, write a short description in the Image Options inside Canvas. For images that are purely decoration, Canvas also offers a way to mark as decorative. This guide explains writing alt text for your Canvas course images:

Add context: Edit common numbering used in generic files names, such as 143228942.jpeg to a meaningful description.
Be specific: Relate the description to the intended message of the imagery - grey rock measuring 1.5 inches rather than grey rock next to a ruler.
Keep it concise: Describe the image clearly and concisely in 1-3 sentences or around 125 characters.
Avoid redundancy: No need to repeat information provided in the surrounding text.
Determine if decorative: If redundant to the text, or only used to beautify your content, mark the image as decorative.

Add Alt Text During Image Upload

You can add alt text during the RCE image upload process. Image uploads through the RCE are automatically added to the Uploaded Media folder located in Files.

Step 1: Upload an Image

From anywhere in Canvas has the RCE, select Images represented with a picture icon.
Click Upload Image.

Step 2: Enter Alt Text or Mark Decorative

Once you've selected an image, type your meaningful description in the Attributes option for Alt Text.
If your image is only for decoration or the text already explains the information shown in the image, check the box for Decorative Image.
Do not use generic file names or repeat information already stated in the surrounding text.
Click Submit to save your work.

Mark Decorative During Upload to Canvas Files

If staying organized is important to you, you can upload images in the Files feature to use folders.

Step 1: Upload to Files

Open Files on the course navigation menu, then either click the Upload button to select an image or drop the file into the upload space.

Step 2: Mark Decorative

Images in the Files location are marked decorative unless you share Files with students. If Files is made available to students, images require alt text.

Step 3: Insert Images Elsewhere

Once you add the image to a place in your course seen by students, enter appropriate alt text or mark decorative.

Edit Alt Text

You can easily edit the alt text of any image in Canvas or mark it decorative.

Select the image to display the Image Options button.
Click the Image Options button to open a slide out tray.
Be sure to click Done to save any changes.

Alt Text in Canvas Video

Alt Text in Canvas FAQ

Do I need to add alt text if the image has words on it?

Yes, images with text on them must include alternative text so that Canvas and screen readers properly share the information with students. An exception is when the image is repeating text in the content, making it repetitive - in this case, the image is then marked decorative.

Why is my Ally Accessibility Report low and indicating I need to add alt text to images in Files?

Your accessibility score is negatively impacted if image files are not marked decorative or given alt text in Files since this feature can be made available to students. While you can use a single image file in multiple places, alt text is uniquely managed in each place you view the image. This means you can mark images as decorative in Files to raise your Ally score, while writing alt text for the same image in other parts of your course.

Do I need to add alt text to an image I use more than once?

Yes, as the use of an image can change depending on where it's used within a course and instructors need to adjust the alt text to represent different context. You must add alt text to an image each time you use it as alt text doesn't get saved to the image file.