Category: WCAG Principles and Conformance

Conformance Level AA

Also known as: Level AA, WCAG Level AA, WCAG 2 Level AA

Simply put

Conformance Level AA is one of three levels defined in the Web Content Accessibility Guidelines (WCAG) that describe how fully a web page meets accessibility requirements. To reach Level AA, a page must satisfy all of the Level A requirements plus the additional Level AA requirements, or provide a conforming alternate version. It is the level most commonly cited as a target by organizations and referenced in laws and policies, though meeting it does not by itself guarantee an accessible experience for every user or immunity from legal claims.

Formal definition

Under WCAG, Level AA is the intermediate of three conformance levels (A, AA, and AAA). For Level AA conformance, a web page must satisfy all applicable Level A and Level AA success criteria, or a conforming alternate version of the page must be provided that meets those criteria. Level AA is inclusive of Level A, so all Level A success criteria must also be satisfied. Note that specific success criteria and their level assignments differ across WCAG versions (2.0, 2.1, 2.2); practitioners should confirm which version and criteria apply to their context. In the US federal context, Section 508 guidance directs authors and developers to assess conformance to WCAG 2.0 Level AA. Level AA is frequently identified as the level most commonly targeted in organizational policies and referenced in legal contexts, but conformance is distinct from usability and from legal compliance: automated testing detects only a portion of issues, and manual and assistive technology testing are required. This entry is not legal advice; applicable requirements evolve through regulation and case law, and readers should consult qualified legal counsel or current agency rulemaking.

Why it matters

Conformance Level AA is the benchmark most frequently referenced when organizations, laws, and policies describe their accessibility targets. Because it builds on Level A and adds further requirements, it represents a more comprehensive baseline for removing barriers than the minimum level alone, while remaining more broadly achievable than the stricter Level AAA. This is why many organizations adopt Level AA as their internal standard and why it commonly appears in legal and regulatory discussions of web accessibility.

In the US federal context, Section 508 guidance directs authors and developers to assess conformance to WCAG 2.0 Level AA, giving the level particular significance for federal agencies and covered federal contexts. Level AA is also frequently cited as a target in settlements and policies outside the federal sphere, though it is important to understand that referencing WCAG in a legal context is generally a benchmark rather than a codified, universal legal mandate. The specific requirements that apply depend on the WCAG version and the authority involved.

Reaching Level AA does not by itself guarantee an accessible experience for every user or immunity from legal claims. Conformance is distinct from usability and from legal compliance: automated testing detects only a portion of accessibility issues, so manual review and assistive technology testing are needed to evaluate real-world use. Organizations treating Level AA as a meaningful goal should therefore pair conformance efforts with hands-on testing and should recognize that applicable requirements continue to evolve through regulation and case law.

Who it's relevant to

Compliance officers

Level AA is the level most commonly identified in organizational policies and referenced in legal contexts, making it a practical benchmark for setting internal accessibility standards. Compliance officers should confirm which WCAG version applies to their obligations and recognize that conformance is not the same as legal compliance; this entry is not legal advice, and qualified legal counsel should be consulted on applicable requirements.

Accessibility engineers and developers

Engineers must ensure a page satisfies all applicable Level A and Level AA success criteria, or provides a conforming alternate version. Because a single failing criterion prevents conformance at the level, and because automated testing detects only a portion of issues, engineers should combine automated tooling with manual and assistive technology testing and verify the correct WCAG version for their context.

UX designers

Level AA requirements shape design decisions that affect how broadly a page can be used. Designers should treat Level AA as a target that supports usability but should not assume conformance alone guarantees an accessible experience for every user; hands-on evaluation with assistive technologies remains important.

Legal counsel

Level AA is frequently cited as a target in laws, policies, and settlements, and Section 508 guidance directs assessment against WCAG 2.0 Level AA in covered federal contexts. Counsel should note that WCAG references often function as benchmarks rather than universally codified mandates, that requirements evolve through regulation and case law, and that conformance does not guarantee immunity from claims.

Business leaders

Adopting Level AA as an organizational standard aligns with the level most commonly targeted in policies and legal discussions. Leaders should understand that achieving conformance requires ongoing testing beyond automated checks and does not by itself ensure legal safety, and should plan for evolving requirements accordingly.

Inside Conformance Level AA

Definition of Level AA

Level AA is the middle of the three WCAG conformance levels (A, AA, and AAA), published by the W3C through the Web Accessibility Initiative. To claim AA conformance, content must satisfy all applicable Level A success criteria plus all Level AA success criteria for the WCAG version in question.

Cumulative conformance model

AA conformance builds on Level A; it is not an alternative to it. Meeting AA means meeting every Level A criterion as well, whereas AAA (the highest level) would additionally require the AAA criteria, which the W3C notes are not recommended as a blanket requirement for entire sites.

Version-specific criteria

The specific success criteria that make up Level AA differ between WCAG 2.0, 2.1, and 2.2. Later versions added criteria (for example, several addressing mobile, low vision, and cognitive needs were introduced in 2.1, with further additions in 2.2), so a valid AA claim should identify which WCAG version it references.

Common benchmark for policy and settlements

WCAG 2.x Level AA is the level most frequently cited as a target in accessibility policies, procurement standards, and legal settlements. It is often referenced as a benchmark rather than a universally codified legal rule; specific requirements arise from particular regulations, agency guidance, or settlement agreements and should be attributed accordingly.

Relationship to other authorities

Level AA is a technical target that various authorities may reference, but it is distinct from the legal frameworks themselves. Section 508 (federal agencies), Title II of the ADA (state and local government), and Title III of the ADA (public accommodations) each have their own scope, and where they point to WCAG they do so through their own rules or guidance.

Common questions

Answers to the questions practitioners most commonly ask about Conformance Level AA.

Does meeting WCAG Level AA make my website legally compliant with the ADA?

Not automatically. WCAG Level AA is a technical benchmark published by the W3C, while the ADA is a US civil rights law that does not itself contain detailed web technical specifications. Courts, settlements, and agency guidance have often referenced WCAG Level AA as a benchmark, but conformance does not guarantee immunity from legal claims. Whether a specific WCAG version or level applies to your situation can depend on the applicable authority (for example, Title II or Title III of the ADA), any relevant regulation or settlement, and evolving case law. For questions about legal exposure, consult qualified legal counsel; this entry is not legal advice.

If my site passes automated accessibility checks at Level AA, is it fully accessible?

No. Passing automated checks does not guarantee an accessible experience for all users. Automated testing detects only a portion of potential issues, and meeting WCAG success criteria on paper does not ensure usability in practice. Manual evaluation and testing with assistive technologies are generally required to assess conformance and real-world accessibility. Level AA conformance and genuine usability are related but distinct.

What is the difference between Level A, AA, and AAA?

WCAG organizes its success criteria into three conformance levels. Level A represents the most basic requirements, Level AA builds on Level A and is the level most commonly cited as a target, and Level AAA is the most stringent. To claim Level AA conformance, content generally must satisfy all Level A and all Level AA success criteria. Level AAA is not typically recommended as a blanket requirement for entire sites.

Which WCAG version should I target for Level AA?

WCAG exists in multiple versions, including 2.0, 2.1, and 2.2, and success criteria differ across them, with later versions adding criteria not present in earlier ones. When targeting Level AA, it is important to specify which version you are conforming to, because a Level AA claim is version-specific. The appropriate version may depend on applicable regulation, agency guidance, or settlement terms, so confirm current requirements rather than assuming a single version applies universally.

How do I verify that my content meets Level AA?

Verification generally combines automated tools with manual review and testing using assistive technologies such as screen readers and keyboard-only navigation. Because automated tools catch only some issues, manual evaluation against the relevant Level A and Level AA success criteria for your chosen WCAG version is commonly needed to support a conformance determination.

Does Level AA apply the same way across all US accessibility laws?

Not necessarily. The authorities differ in scope: Section 508 applies to federal agencies and covered federal contexts, Title II of the ADA applies to state and local government, and Title III applies to places of public accommodation. How a Level AA benchmark is referenced can vary by authority, regulation, and case law. Determine which authority applies to your organization and consult qualified legal counsel and current agency rulemaking for specifics.

Common misconceptions

Meeting WCAG Level AA guarantees legal compliance and immunity from claims.

Conformance to Level AA is distinct from legal compliance. Meeting the success criteria does not by itself guarantee an accessible experience for all users or immunity from legal claims. Legal obligations arise from specific laws, regulations, agency guidance, and case law, and organizations should consult qualified legal counsel.

The ADA legally mandates WCAG 2.x Level AA.

The ADA is a US civil rights law and does not itself contain detailed web technical specifications. WCAG Level AA is commonly cited as a benchmark in settlements and guidance, but any binding requirement to meet a specific version and level comes from a particular regulation, agency rule, or settlement and should be attributed to that source.

Passing automated tests confirms Level AA conformance.

Automated testing detects only a portion of accessibility issues. Achieving and verifying Level AA generally requires manual evaluation and testing with assistive technologies in addition to automated checks.

Best practices

Specify the exact WCAG version (for example 2.0, 2.1, or 2.2) alongside any Level AA target, since the applicable success criteria differ between versions.

Treat Level A criteria as included in any AA effort, verifying that all applicable Level A and Level AA criteria are met rather than addressing AA criteria in isolation.

Combine automated testing with manual review and assistive technology testing, recognizing that automated tools catch only some issues.

Distinguish conformance from legal compliance and usability in internal documentation, and consult qualified legal counsel regarding obligations under the relevant authority (such as Section 508, ADA Title II, or ADA Title III).

When referencing settlements, regulations, or agency guidance that cite Level AA, attribute the requirement to that specific source rather than treating AA as a universal legal mandate.

Monitor for evolving requirements, since accessibility obligations change through ongoing regulation and case law and newer WCAG versions may introduce additional Level AA criteria.