Contrast Ratio (WCAG Standards)

The luminance difference between text (or UI elements) and their background, measured against WCAG AA (4.5:1) and AAA (7:1) standards for legibility.

In games, this means

Grey text on a slightly lighter grey background, white text over a complex game world, or yellow tooltips on cream backgrounds fail contrast standards and are unreadable for players with low vision or in bright environments. WCAG AA (4.5:1) is the minimum for body text. Games that pass these thresholds are readable by significantly more players without extra accessibility settings.