brlebtag / BestFg

Algorithm to find the best foreground color based on the specified background color.

BestFg

Algorithm to find the best foreground color based on the specified background color.

Extract RGB components from string:

function extractRGB(str) {
    return [parseInt(str.substr(1, 2), 16), parseInt(str.substr(3 ,2), 16), parseInt(str.substr(5, 2), 16)];
}

Get best foreground color:

function getBestFg(str){
    var rgb = extractRGB(str);
    var r = rgb[0], b  = rgb[1], g = rgb[2];
    
    var yiq = ((r*299)+(g*587)+(b*114))/1000;
    
    return (yiq >= 128) ? 'black' : 'white';
}