Design Principle
Charts cannot rely on color alone; categories and states need text, shape, line style, or direct labels.
Principle Charts cannot rely on color alone; categories and states need text, shape, line style, or direct labels.
Design action Give each series direct labels, distinct line styles/symbols, or text states; keep legends close and high-contrast.
Examples Positive example: Multi-series lines, status distributions, maps, and heatmaps inform decisions rather than decorate. Counterexample: Red and green lines differ only by color.
Apply when Multi-series lines, status distributions, maps, and heatmaps inform decisions rather than decorate. Users need to judge state, scope, risk, or next action quickly.
Source notes Source note: Synthesized from W3C WCAG 2.2, Apple Accessibility, IBM Carbon Accessibility, and accessibility practices in major design systems.
Agent Directive
Give each series direct labels, distinct line styles/symbols, or text states; keep legends close and high-contrast.