Văn Bản Lớn (WCAG)

WCAG defines large text as having inherently better readability due to its size, so it requires lower contrast ratios than normal text. Large text needs only 3:1 contrast for AA and 4.5:1 for AAA, compared to 4.5:1 and 7:1 respectively for normal text. This distinction is important when designing headings, buttons, and navigation elements, which are often rendered in larger sizes. The 18pt/14pt-bold thresholds correspond to the typical sizes where letterforms become recognizable enough that less contrast is needed for legibility.