What this means
The visual parts needed to identify controls or understand graphics generally need at least 3:1 contrast against adjacent colors. Meaning should not depend on color alone.
Passing examples
- A checkbox outline clearly stands out from the form background at 3:1 or more.
- A chart uses labels and different line patterns as well as colors.
- An approval result includes the word 'Approved' and a checkmark, not only green coloring.
Failing examples
- A checkbox border blends into its background at less than 3:1.
- Red and green chart lines have no labels or other way to tell them apart.
- A result is shown only as a colored dot, with no explanation of its meaning.
Words inside buttons still need text contrast. A decorative border is different from a boundary required to identify a control.