wcag color constrast

WCAG contrast ratio measurement and scoring.

API

luminance

Get the contrast ratio between two relative luminance values

Parameters

• a number luminance value
• b number luminance value

Examples

luminance(1, 1); // = 1

Returns number contrast ratio

rgb

Get a score for the contrast between two colors as rgb triplets

Parameters

• a array
• b array

Examples

rgb([0, 0, 0], [255, 255, 255]); // = 21

Returns number contrast ratio

hex

Get a score for the contrast between two colors as hex strings

Parameters

• a string hex value
• b string hex value

Examples

hex('#000', '#fff'); // = 21

Returns number contrast ratio

score

Get a textual score from a numeric contrast value

Parameters

• contrast number

Examples

score(10); // = 'AAA'

Returns string score