Catalog
technology#User Experience#Usability#Inclusive Design#Web

Web Content Accessibility Guidelines (WCAG)

WCAG defines principles and success criteria for accessible web content. Its goal is improved usability and legal compliance across diverse user groups.

The Web Content Accessibility Guidelines (WCAG) define principles and success criteria for making web content accessible.
Established
Medium

Classification

  • Medium
  • Organizational
  • Architectural
  • Intermediate

Technical context

Design systems (e.g., Storybook)Automated testing tools (e.g., axe, Pa11y)Content management systems

Principles & goals

Perceivable: Content must be available to all sensory modalities.Operable: Interactive elements must be accessible and operable.Understandable: Content and operation must be understandable.
Build
Enterprise, Domain, Team

Use cases & scenarios

Compromises

  • Incomplete testing leads to incorrect conformance assessment.
  • Lack of team training reduces sustainable implementation.
  • Focusing only on automation misses user-centered issues.
  • Consider accessibility during design reviews
  • Combine automated and manual testing
  • Implement accessible components once and reuse them

I/O & resources

  • Designs, prototypes, and source code
  • WCAG checklists and success criteria
  • Test environments and assistive technologies
  • Conformance reports and migration plans
  • Accessible component libraries
  • Training materials and policies

Description

The Web Content Accessibility Guidelines (WCAG) define principles and success criteria for making web content accessible. They help developers and organizations plan, assess, and implement accessible user interfaces. WCAG supports legal compliance, inclusive user experiences, and technical interoperability. It is widely adopted as an international standard.

✔

  • Increased reach and better user satisfaction across user groups.
  • Reduction of legal risks by complying with standards.
  • Improved quality and robustness of frontend implementations.

✖

  • Full WCAG conformance can be time- and cost-intensive.
  • Some success criteria require subjective assessment.
  • Legacy systems cannot always be fully adapted without refactoring.

  • Conformance level

    Share of criteria met at A/AA/AAA levels.

  • Automated errors per page

    Number of issues found by tools per page.

  • User test score

    Outcome from qualitative tests with assistive users.

Government websites following WCAG

Many public institutions publish accessibility-compliant sites as legal requirement.

E‑commerce checkout with screen reader support

Examples show how checkout flows are optimized for assistive technologies.

Design systems with accessible components

Organizations integrate WCAG principles into their component libraries.

1

Review WCAG requirements and define scope

2

Adapt design system and audit components

3

Integrate automated tests and plan manual testing

4

Conduct training and embed accessibility in processes

⚠️ Technical debt & bottlenecks

  • Non-semantic HTML structures in legacy code
  • Missing or incorrect ARIA attributes
  • Insufficient test coverage for assistive technologies
Missing design systemInsufficient test coverageLegacy frontends without semantic structure
  • Adding icons without text alternatives
  • Ignoring focus management and breaking keyboard navigation
  • Using color alone to convey information
  • Blindly adopting automated tool results
  • Treating WCAG points in isolation instead of user context
  • Running A/B tests without accessibility considerations
HTML/CSS semantics and ARIA knowledgeExperience with accessibility testing and user testsLegal fundamentals and compliance understanding
Accessibility as a requirement for UI architectureInteroperability with assistive technologiesAuditability and compliance requirements
  • • Legal requirements and deadlines
  • • Limited development resources
  • • Technical limitations from third-party components