WCAG conformance levels A, AA and AAA: what the EAA requires
What the three WCAG conformance levels mean, why AA is the standard the law builds on, and how conformance is actually determined.
The WCAG define three conformance levels: A, AA and AAA. In practice, the question behind them is almost always the same – which one do I need? The short answer under the EU framework is: AA. This article explains what the three levels mean, why AA is the relevant standard, and how conformance is determined at all. For the wider picture, see our WCAG guide.
What the conformance levels mean
The three levels build on one another: A is the lowest, AA the middle, AAA the highest. Each higher level includes the criteria of the lower ones – so AA covers all A criteria plus the additional AA criteria, and AAA covers all of those plus the AAA criteria.
They are not freely chosen “grades” but a classification by how far-reaching your removal of barriers is. Every single WCAG success criterion is assigned to exactly one level. What the WCAG are overall and how they are structured is explained in the WCAG guide.
Level A – the minimum
Level A covers the most basic barriers. Without them, content is simply unusable for some groups of users. This includes things like text alternatives for images, the operability of basic functions by keyboard, avoiding dangerously flashing content, and marking up the page language.
Level A on its own is not legally sufficient – it is the floor beneath the floor, not the goal.
Level AA – the standard
AA is the level that laws around the world, and the EU framework too, require, because it addresses the barriers that matter most in practice. Typical AA requirements are sufficient colour contrast, the ability to enlarge text, consistent navigation, clear labels, and understandable error messages.
AA is at the same time the realistic, achievable goal for a real website. One specific AA point is explored in depth in colour contrast under WCAG; a practical list of the points to check is offered by the EAA compliance checklist.
Level AAA – the highest level
AAA sets the strictest requirements – for example a contrast of 7:1, sign language for videos, or particularly strict rules on understandability and time limits. The W3C itself points out that AAA cannot be met consistently across all content of an entire website, and explicitly recommends not requiring AAA as a blanket requirement for a whole page.
AAA is therefore selective and worth aiming for in individual places – but not a realistic across-the-board obligation. That is precisely why laws do not require AAA in general.
Which level the law requires
The relevant level is AA. The European Accessibility Act requires accessibility but doesn’t name a technology itself; the technical benchmark comes from the harmonised standard EN 301 549, whose currently applicable version v3.2.1 references WCAG 2.1 at Level AA. More on this standard in EN 301 549 explained.
WCAG 2.2 AA is the recommended best practice and the foreseeable future benchmark – the upcoming version of the standard, v4.1.1 (publication expected in 2026), will incorporate it. Today, however, the legally binding floor is 2.1 AA.
One important point to close this section: meeting WCAG 2.1 AA is necessary, but on its own it does not yet guarantee full compliance – because EN 301 549 goes beyond the WCAG. National implementing laws (such as Germany’s BFSG) apply the same benchmark. The legal framework is set out in the European Accessibility Act guide.
How conformance is determined
Two things are decisive here. First, conformance is determined per page – and a complete process, such as a checkout flow, must be conformant all the way through, not just the home page. Second, per level the principle is all-or-nothing: to be “AA-conformant”, a page must meet all A and AA criteria. There is no such thing as “80 % AA” – a single open AA criterion means the page is not AA-conformant.
This is also why automated “scores” can mislead: a high percentage is not proof of conformance. How conformance can be tested reliably is shown in how to test accessibility.
Frequently asked questions
Which WCAG level do I need under the EU framework?
Level AA – via the standard EN 301 549 v3.2.1, which references WCAG 2.1 Level AA. National implementing laws (such as Germany’s BFSG) apply the same benchmark.
Should I aim straight for AAA?
Usually not across the board. The W3C advises against requiring AAA as a blanket requirement for a whole website, because it cannot be met for all content. AA is the goal; individual AAA criteria can make sense in specific places.
Is it enough to meet most of the AA criteria?
No. Conformance is all-or-nothing per level. Even a single unmet AA criterion means the page does not count as AA-conformant.
This guide is not legal advice. For a binding assessment of your specific case, consult a qualified professional.