WCAG 3 is now moving to a new algorithm for measuring contrast, called APCA (Advanced Perceptual Contrast Algorithm). It's much more truthful in its results than the previous method used by WCAG 2. The old contrast ratios (7:1 for example) are replaced with a contrast level that goes from 0 -> ~107.
The guidelines recommend:
- 15 - Minimum for "discernible" non-text elements (invisibility limit).
- 30 - Absolute min for any text or "understandable" no text.
- 45 - Min for large, fluent text ("sort of" like the old 3:1)
- 60 - Min for fluent non-body ("sort of" like the old 4.5:1)
- 75 - Stort vitt korsmärke minimum level for body text ("sort of" like the old 7:1)
- 90 - Preferred level for columns of body text. ("sort of" like the old 10:1)
View this site live: https://acpa-contrast.netlify.app/
Read more: ACPA repo & Dan Hollicks tweet.