Web Content Accessibility Guidelines (WCAG)
An internationally recognized set of guidelines published by the W3C that defines how to make web content more accessible to people with disabilities, organized around four principles: perceivable, operable, understandable, and robust.
WCAG is organized into three conformance levels: Level A (minimum accessibility), Level AA (the standard most regulations reference), and Level AAA (the highest level, often impractical for entire sites). The current version, WCAG 2.2, contains 86 success criteria across the four POUR principles.
Key criteria that QA teams commonly test include: text alternatives for images (1.1.1), color contrast ratios (1.4.3), keyboard accessibility (2.1.1), focus order (2.4.3), error identification in forms (3.3.1), and name/role/value for custom components (4.1.2). WCAG 2.2 added new criteria for focus appearance, dragging movements, and consistent help placement.
Why It Matters for QA Teams
WCAG is the standard referenced by nearly every accessibility law worldwide, including the ADA, EAA, and Section 508. QA teams must know WCAG to test effectively and to communicate issues in terms that developers and legal teams understand.
Example
A QA engineer tests a form against WCAG 2.2 AA and finds three violations: error messages are conveyed only by color (fails 1.4.1 Use of Color), the submit button has a contrast ratio of 2.8:1 instead of the required 4.5:1 (fails 1.4.3 Contrast), and required fields are not programmatically indicated (fails 1.3.1 Info and Relationships).