What is WCAG?
WCAG, the Web Content Accessibility Guidelines, is the W3C standard for making websites usable by people with disabilities. It is organised around four principles, perceivable, operable, understandable and robust, with testable success criteria at levels A, AA and AAA. Most laws and policies point to level AA.
Versions
WCAG 2.1 added criteria for mobile, low vision and cognitive needs, and WCAG 2.2, published in 2023, added more on visible focus, target size and accessible sign-in. Each version builds on the last, so content that meets 2.2 generally meets the earlier versions too.
What level AA asks for in practice
Text contrast of at least 4.5 to 1 for normal text, full keyboard access with a visible focus, text alternatives for images, captions for video, clear labels on form fields and text that can be enlarged to 200 percent without breaking the layout.
Why it matters beyond compliance
Accessible sites work better for everyone: on small screens, in bright light, on slow connections or for people in a hurry. Accessibility rules built into a design system are fixed once for every page.
