Research Guides: Free Image Collections: Accessibility Tools for Images

Basic Guidelines

Online instructional materials are required to be accessible to all users. This page offers detailed information about using images; see the "Accessibility Resources" page for more complete information.

Some basic guidelines for making your webpages properly accessible:

Images need alt-text, which is a short description of the image. Learn how to add alt-text in the box below.
If your image contains necessary information (such as a graph or chart), you will need to make that information available in another way as well.
When choosing colors for your materials, keep color-blindness in mind and don't use colors to convey information (such as using red and green to show different categories). Or use these universal color-blindness-friendly palettes!
Learn principles of universal design that will make your materials easier for everyone to use. Read WebAIM's "Introduction to Accessibility Design" to get started.

Visual Tools

WAVE: Web Accessibility Evaluation Tool
Enter a URL and WAVE will analyze it for accessibility issues.
Colblindor: All About Color Blindness
"Colblindor at www.color-blindness.com presents all you ever wanted to know, learn and try out concerning color blindness."
WebAIM Contrast Checker
Check the color contrast on your pages.
Vischeck
Vischeck simulates color blind vision.
Daltonize
Daltonize corrects images for color blind users.

More Resources

Resources for more in depth study.

WebAIM - Alternative Text Guide
"Through the use of examples, this article [presents WebAIM's] experienced interpretation of appropriate use of alternative text."
WebAIM - Assessible Images
Guide to creating accessible images beyond just adding alt text.
HOW MUSEUMS ARE MAKING ARTWORKS ACCESSIBLE TO BLIND PEOPLE ONLINE

How to add alt-text to an image

In Canvas, when you add an image, a box pops up asking for certain information. Under "Attributes," you're asked to provide the alt-text, which is a short description of the image that will be read by a screenreader. If the image is purely decorative (for example a line of scrollwork) and should not be described, check the "Decorative Image" option. Most images should be described.

The same principle holds true for any web design; if you have a blog or are designing a webpage, make sure to add alt-text to your images. Virtually all web design software and blogging tools include this option under "Image Properties" or "Edit Image." To learn how to write alt-text see WebAim's Alt-text guide.