What this means
Contrast is the difference between text and its background. Ordinary text needs at least 4.5:1. Large text needs at least 3:1. Large means at least 18 points, or 14 points when bold. The ratio must be measured, not guessed.
Passing examples
- Body text uses a color pair measured at 7:1.
- Small captions and button text meet 4.5:1 against their own backgrounds.
- A large 18-point heading measures 3.5:1.
- Text over a photograph has a solid background that keeps every word above the required contrast ratio.
Failing examples
- Small pale-gray text on white measures 2:1.
- Words disappear into a bright part of the photograph behind them.
- A small button label measures 3:1: sufficient for some large text, but insufficient for this small label.
- A link meets contrast before hovering but becomes too faint in its hover state.
If you are unsure whether text is large, use 4.5:1. An approved color pair remains useful only while both colors stay the same.