Convert bytes to human readable format, based on code here: http://stackoverflow.com/questions/4498866/actual-numbers-to-the-human-readable-values/4506030#4506030

GetHumanSize.js

var SizePrefixes = ' KMGTPEZYXWVU';
GetHumanSize = function(size) {
    if(size <= 0) return '0';
    var t2 = Math.min(Math.round(Math.log(size)/Math.log(1024)), 12);
    return (Math.round(size * 100 / Math.pow(1024, t2)) / 100) +
        SizePrefixes.charAt(t2).replace(' ', '') + 'B';
}