Validar CPF por javascript

cpf.js

var CPF = (function () {
    var eleven = 11;


    function mod(n) {
        var t = eleven,
            a = n % t;

        return (a < 2 ? 0 : t - n % t) + '';
    }


    return {
        digits: function (numbers) {
            var first = 0,
                second = 0,
                result = '';

            for (var i = 0, t = 9, n = eleven; i < t; i += 1, n -= 1) {
                var j = numbers[i] | 0;

                first += (n - 1) * j;
                second += n * j;
            }

            result = mod(first);
            second += 2 * result[0] | 0;

            result += mod(second);

            return result;
        },
        check: function (cpf) {
            var numbers = (cpf + '').replace(/[^0-9]/g, ''),
                first = 0,
                second = 0;
            
            if (numbers.length === eleven && numbers !== Array(11 + 1).join('0')) {
                return numbers.substr(-2) === this.digits(numbers);
            }
     
            return false;
        },
        generate: function (masked) {
            var numbers = [],
                result = '',
                cpf = '';

            for (var i = 0, t = 9; i < t; i += 1) {
                numbers[i] = ((Math.random() * 9) + 0.5) | 0;
            }

            result = numbers.join('');
            cpf = result + this.digits(result);

            if (masked) {
                cpf = this.mask(cpf, true);
            }

            return cpf;
        },
        mask: function (cpf, skipCheck) {
            if ((skipCheck !== false && this.check(cpf)) || skipCheck) {
                var numbers = (cpf + '').replace(/[^0-9]/g, ''),
                    regex = /(\d{3})(\d{3})(\d{3})(\d{2})/.exec(numbers);

                return regex[1] + '.' + regex[2] + '.' + regex[3] + '-' + regex[4];
            }

            return cpf;
        }
    };
}());



> CPF.generate();
'73865473822'
> CPF.mask('73865473822');
'738.654.738-22'
> CPF.generate(true);
'946.502.934-30'
> CPF.digits('111222333');
'96'
> CPF.check('111.222.333-96');
true