The Web Content Accessibility Guidelines (WCAG) are the international standard for making websites usable by people with disabilities. They are published by the World Wide Web Consortium (W3C). Level AA of WCAG 2.1 is the benchmark most organizations aim for, and the level referenced by many laws and policies.
Levels A, AA and AAA
WCAG success criteria are grouped into three levels. A covers the most basic requirements. AA adds important requirements such as colour contrast and is the common target. AAA is the strictest and is not usually required for entire websites.
2.0, 2.1 and 2.2
Each version builds on the last. WCAG 2.1 added criteria for mobile, low vision and cognitive accessibility. Meeting 2.1 AA also meets 2.0 AA. WCAG 2.2 adds further criteria, and aiming for it is good practice for new work.
The four principles
- Perceivable: people can see or hear the content, for example through text alternatives for images and captions for video.
- Operable: everything works with a keyboard, people have enough time, and nothing flashes dangerously.
- Understandable: content and navigation are predictable and forms help people avoid and fix mistakes.
- Robust: the code works reliably with browsers and assistive technologies such as screen readers.
Requirements that catch most websites
- Text alternatives for meaningful images (how to write alt text)
- Colour contrast of at least 4.5:1 for normal text (contrast guide)
- Every function usable with a keyboard, with a visible focus indicator
- Logical heading structure
- Labelled form fields and clear error messages (accessible forms)
- Captions for video with speech
- Content that can be zoomed to 200% and reflows on small screens
- A way to pause moving or auto-updating content
How it relates to the law
In Ontario, the AODA references WCAG 2.0 Level AA for many organizations’ websites. In the United States, WCAG 2.1 AA is the standard the Department of Justice adopted for state and local government websites and the common benchmark for businesses under the ADA.
Every site we build is tested to WCAG 2.1 AA, and we audit existing sites too. Ask about an accessibility audit.
Need a hand?
TheWebsiteMakers.ca is a Toronto-based team with 19+ years of experience building websites for businesses across Canada and the US. We design accessible websites, host them on servers we manage ourselves, and look after them every month. Get a free, no-obligation quote.