Calculate a WCAG contrast ratio based on a foreground and background color

Note: This module only accepts rgb values for simplicity. If you're trying to obtain a ratio for hex, consider using a helper function/module to first convert your hex strings to an rgb tuple.

$ npm i -S contrast-ratio

const ratio = require("contrast-ratio");

ratio([255, 255, 255], [0, 0, 0]);
// -> 21

ratio([0, 0, 255], [255, 255, 255]);
// -> 8.59

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