- WCAG 1.0 Checkpoint
- 2.2 Ensure that foreground and background color combinations provide sufficient contrast when viewed by someone having color deficits or when viewed on a black and white screen
- WCAG 2.0 Success Criteria
- 1.4.1 Text or diagrams, and their background, have a luminosity contrast ratio of at least 5:1
- 1.4.3 Text or diagrams, and their background, have a luminosity contrast ratio of at least 10:1
Understanding WCAG 2.0: examples of evaluation tools that implement the luminosity contrast ratio algorithm.
