Lesson 2 / 25

WCAG standards

Learn the Web Content Accessibility Guidelines—the industry standard.

WCAG versions & levels

WCAG 2.1 is the current standard (2.0 exists, 3.0 in draft). Three levels: A (basic), AA (enhanced—legal minimum in most regions), AAA (optimal). Each level has four principles: Perceivable, Operable, Understandable, Robust (POUR).

POUR principles

Perceivable: users can see/hear content (color + text, captions). Operable: keyboard, voice, switch—no mouse-only interactions. Understandable: clear language, predictable design, error recovery. Robust: works with assistive tech (screen readers, voice control, etc.).

Practical compliance

Most organizations target WCAG 2.1 AA. This requires contrast ratios of 4.5:1, keyboard navigation, alt text, proper forms, and ARIA where needed. AAA is ideal but not always required.

Where to learn more

Visit w3.org/WAI/WCAG21 for the full specification, webam.org for checklists, and level access for training materials.

Compliance audit

Third-party audits provide formal compliance assessment. Useful for legal proof and improvement recommendations.