Template:Color contrast ratio/doc

This template returns the color contrast ratio between the two colors provided. It accepts two parameters, which can be a standard RGB hex color code or a standard HTML color or CSS "orange" (=  ). Color names and hex letters are case-insensitive (i.e. they may be upper- or lower-case).

WCAG 2.0
As a guide to selecting foreground and background colors for text, the Web Content Accessibility Guidelines 2.0 (guideline 1.4) classifies contrast ratios for ordinary text as follows:

Normal wiki-text is rendered by common browsers at roughly 9.5 to 10.5 pt (12.5 to 14 px), depending on skin. Text would need to be about 180% or 140% bold to qualify as "Large" for WCAG purposes.