The contrast ratios themselves, and why 4.5 to 1 is the floor for body text, are covered in "Accessibility and contrast ratios" in the Colour module. For a brand palette, the two lower thresholds matter as much. Large text needs 3 to 1, and a separate 3 to 1 applies to interface components such as buttons, form fields and icons, which decides whether a pale brand colour can carry a headline or a button border at all.
Try it
Put a brand colour behind white text and see whether it passes. If it fails, darken it here until it does.
Open till late, every day
Small type is where contrast fails first. A heading this size can get away with a pale colour that a line of body text cannot, which is why the rules give large text a lower floor.
2.78:1
- Body text · needs 4.5:1
- Large text · needs 3:1
- Body text, strictest (AAA) · needs 7:1
The rest of this is for members.
You have read the opening of this lesson. The rest of it comes with a membership.
One membership covers all four courses and Brands.
- All lessons in the four Learn courses
- All brand breakdowns in the Brands section
- All quizzes, flashcards and crosswords
- An AI teacher on every lesson, for up to 60 questions a day
- All course material published during the membership
Price
Membership is from $12 a month on the Yearly plan, which is charged at $144 once a year. Lifetime access is $59, paid once.Membership is from ₹200 a month on the Yearly plan, which is charged at ₹2,400 + GST once a year. Lifetime access is ₹3,999 + GST, paid once.