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Contrast Ratio

The difference in luminance between text and background colors, required to be at least 4.5:1 for WCAG AA compliance.

Last updated: December 16, 2025

Definition

The difference in luminance between text and background colors, required to be at least 4.5:1 for WCAG AA compliance.

Why It Matters

Understanding this concept is crucial for implementing accessible, user-friendly interfaces that comply with web standards.

Examples

Common real-world implementations and usage patterns for this concept.

Best Practices

  • Follow WCAG guidelines when applicable
  • Test with assistive technologies
  • Document your implementation decisions

Related Topics

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Contrast Ratio | VertaaUX Learn | Vertaa