This document is a general checklist of potential accessibility issues that can be used to review a site for usability. Additional topic-specific checklists will be created that go into more detail.

Landmarks

The following HTML 5 elements function as landmarks that can be used by assistive technology to navigate a website.  

ARIA roles can be used to create landmarks on elements that aren't inherently landmarks:

Language Support

Document Outline

Links

Images

Javascript

Forms

Media (Audio and Video)

Providing text alternatives makes the audio information accessible to people who are deaf or hard of hearing. This also goes for search engines who are deaf and hard of hearing as well.

Color and Contrast

Best done early in the process, by ensuring that the foreground and background colors of your site have sufficient contrast you will help make your site more readable for everyone. Contrast Ratio is one tool for checking the contrast of your colors for both standard vision and color deficient user.

Test against different types of color blindness with a tool like http://colorfilter.wickline.org/.

If you are on a Mac, another option is Michel Fortin's, Sim Daltonism color blindness simulator.

Keyboard navigation

Motion

Testing

Navigating your site using a range of tools, such as just the keyboard or a screen reader, will help you understand how a blind, low-vision, or limited-mobility user will experience it.

Tools