Writing on color contrast
Every ratio in these articles is computed by the same engine that runs the scanner, at the moment the page renders. None of them is typed by hand, so none of them can be a typo.
- 2 minWCAG, typography, contrast
Your 20px heading is not large text
WCAG's large-text relief starts at 24px, or 18.66px at weight 700. Everything below that needs the full 4.5:1, and the gap is where most hand-checked palettes fail.
- 2 minbrand, buttons, contrast
White text on your brand color almost certainly fails
Most brand colors are too light to carry white text at 4.5:1. The fix is usually dark text on the brand color, not a different brand color.
- 2 mintooling, contrast, testing
Why two contrast checkers give you different answers
The ratio is fixed arithmetic, so disagreements are never about the maths. They are about which two colors the tool thinks it is measuring.