WCAG is the shared language used by auditors, legal teams, designers, and engineers when talking about accessibility requirements. It defines testable success criteria and maps them to conformance levels (A, AA, AAA).
Why WCAG matters
Most regulations and procurement frameworks align with WCAG AA. If your team ships features without WCAG alignment, you introduce legal risk and exclude users.
How WCAG works
WCAG is organized around four principles: content must be Perceivable, Operable, Understandable, and Robust (POUR). Under each principle, individual success criteria define what must be true for a page or flow.
In practice, teams typically target AA:
- A covers foundational blockers.
- AA covers broad usability expectations and is the most common legal target.
- AAA is aspirational for many organizations.
Code examples
<!-- Low contrast text: fails WCAG 1.4.3 -->
<p style="color:#8a8a8a;background:#ffffff">Terms and conditions apply.</p><!-- Improved contrast -->
<p style="color:#4a4a4a;background:#ffffff">Terms and conditions apply.</p>Automated validators help by catching recurring WCAG-related defects at scale, while manual audits confirm behavior that tools cannot reliably infer.
Related terms
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