Level A
All Level A success criteria must be satisfied for Level A conformance.
UNDERSTANDING WCAG
WCAG explained
Understand the purpose of WCAG, its four principles, and where to find the official guidance.
UNDERSTAND THE STRUCTURE
Four principles. Testable requirements.
The Web Content Accessibility Guidelines (WCAG) provide a shared standard for making web content more accessible to people with disabilities.
Principles describe the foundations. Guidelines group related goals. Success criteria provide testable requirements, each assigned a conformance level.
For a review, work from the criterion’s full wording. Supporting explanations help you understand its intent and application.
Read the W3C WCAG overview (opens in a new tab)The four principles
- Perceivable
- People can perceive information, including through alternatives to visual or audio content.
- Operable
- People can use controls and navigate the experience.
- Understandable
- People can understand the information and how the interface works.
- Robust
- Content works with user agents, including assistive technologies.
UNDERSTAND THE LEVELS
A, AA, and AAA build on one another.
A conformance level identifies a set of requirements. It is not a percentage score or a severity rating for an individual finding.
Level AA
All Level A and Level AA success criteria must be satisfied for Level AA conformance.
Level AAA
All Level A, AA, and AAA success criteria must be satisfied for Level AAA conformance. W3C does not recommend requiring AAA for entire sites as a general policy.
Keep the version and scope clear
State the WCAG version and target level, for example WCAG 2.2 Level AA. Conformance applies to complete pages and complete processes, alongside the other conformance requirements. Checking selected components alone does not establish page conformance.
Read the WCAG 2.2 conformance requirements (opens in a new tab)CONNECT THE REQUIREMENT TO THE TASK
Read the requirement. Examine the experience.
Consider a delivery form with a field labelled “Details”. A customer may not know whether to enter an address, delivery instructions, or something else.
Example: a descriptive field label
Success Criterion 2.4.6, Headings and Labels, is Level AA. It concerns whether headings and labels describe their topic or purpose. In this example, “Delivery instructions” communicates the field’s purpose more clearly.
This criterion does not cover every aspect of a form label. Whether a label is provided and how it is associated with a control involve other requirements. Review the relevant criteria together.
Read Understanding Headings and Labels (opens in a new tab)A practical reading sequence
- Read the complete success criterion, including exceptions and defined terms.
- Use its Understanding page to explore the intent and examples.
- Inspect and test the actual content or interaction.
- Record the evidence and user impact, then verify any proposed change.
Use the supporting resources together
The standard sets the requirements. Understanding pages explain them, and Techniques describe possible approaches. A listed technique is not the only way to satisfy a criterion.
Open the WCAG 2.2 Quick Reference (opens in a new tab)KEEP LEARNING
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