Legibility & Contrast

Text sizes

• Body text: 16 px+ web; scale with viewport and distance.
• Headings: clear hierarchy, at least 1.2x step.

Contrast

• Target WCAG 2.2 AA minimums; AAA for small/critical text.
• Avoid low-contrast placeholder text; ensure disabled states still readable.

Spacing & line length

• Line height 1.4–1.6; 45–90 CPL (characters per line).
• Generous letter/word spacing improves scanning and dyslexia readability.

Testing

• Test in bright sunlight and dark mode; simulate low vision.
• Verify contrast with tooling in design and code CI.

References

• WCAG 2.2 — Contrast (Minimum) 1.4.3; Non-text Contrast 1.4.11: https://www.w3.org/TR/WCAG22/
• W3C WAI — How to Meet WCAG: https://www.w3.org/WAI/WCAG22/quickref/
• B. Schneiderman et al. — Designing the User Interface (visibility & legibility).