What contrast ratio do I need to pass WCAG?

WCAG 2.1 requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text (18pt, or 14pt bold) to meet AA. The stricter AAA level requires 7:1 for normal text and 4.5:1 for large text.

How is the contrast ratio calculated?

The ratio is (L1 + 0.05) / (L2 + 0.05), where L1 and L2 are the relative luminance of the lighter and darker colors. Relative luminance is computed from the sRGB values using the WCAG formula, so results match other compliant tools.

Do team color pairings pass contrast requirements?

It varies. Many team primary-on-white or white-on-primary pairings pass AA comfortably, but some combinations — light gold on white, or two similar mid-tones — fail. Loading a team pairing shows exactly where each combination lands.

Contrast Checker

Test any foreground and background color against WCAG 2.1 AA and AAA thresholds in real time. Type hex values directly, or load a real team pairing to see how its colors score together.

Foreground (text)

Background

Or load a team pairing

Sample headingThe quick brown fox jumps over the lazy dog.Small caption text at 14 pixels

9.55:1contrast ratio

AA · Normal textPass

AA · Large textPass

AAA · Normal textPass

AAA · Large textPass

Frequently asked questions

What contrast ratio do I need to pass WCAG?: WCAG 2.1 requires a contrast ratio of at least 4.5:1 for normal text and 3:1 for large text (18pt, or 14pt bold) to meet AA. The stricter AAA level requires 7:1 for normal text and 4.5:1 for large text.
How is the contrast ratio calculated?: The ratio is (L1 + 0.05) / (L2 + 0.05), where L1 and L2 are the relative luminance of the lighter and darker colors. Relative luminance is computed from the sRGB values using the WCAG formula, so results match other compliant tools.
Do team color pairings pass contrast requirements?: It varies. Many team primary-on-white or white-on-primary pairings pass AA comfortably, but some combinations — light gold on white, or two similar mid-tones — fail. Loading a team pairing shows exactly where each combination lands.