Standards

WCAG levels A, AA and AAA explained

Three conformance levels, one targeted by law. Understand what each covers and why AA is the target.

WCAG classify their success criteria into three conformance levels. Knowing which one concerns you avoids aiming too low or too high.

Level A: the minimum

Level A covers the most blocking obstacles. It is an indispensable baseline, but insufficient on its own for most legal obligations.

Level AA: the legal target

Level AA adds essential requirements such as colour contrast and fully usable navigation. It is the level chosen by the European Accessibility Act through the EN 301 549 standard, and by nearly all regulations.

Level AAA: the most demanding

Level AAA aims for maximum accessibility. It is generally not required across a whole site, because some criteria are not achievable for all content types.

In practice, targeting WCAG 2.2 level AA is the right objective for compliance.