How do gray text and dark backgrounds fare in WCAG contrast ratios?

The thresholds don't change. 1.4.3 Contrast (Minimum) asks for 4.5:1 for normal text and 3:1 for large text, and 1.4.11 Non-text Contrast asks for 3:1 for the visual information that identifies controls. The formula doesn't care which color is lighter, so light text on dark uses the same calculation as dark text on light. Pure white on pure black gives 21:1, the maximum. Every other pair scores lower on that scale. Text on photos is covered on the text over images page, so this page sticks to solid backgrounds.

#767676 is one of the few grays that pass 4.5:1 on both pure black and pure white. On pure black it reaches 4.62:1, and on white it reaches 4.54:1. On #121212 the same gray gives 4.12:1, which misses 4.5:1 for normal text but still clears 3:1 for large text. A soft dark background raises the bar for gray text. Darker gray #4D4D4D reaches only 2.22:1 on #121212, which fails even the 3:1 bar.