jquery.password-strength.js

$(document).ready(function () {

    $('#password').keyup(function () {
        $('#result').html(checkStrength($('#password').val()));
    });

    $('#password_confirmation').keyup(function () {
        $('#confirm_result').html(checkMatch($('#password').val(), $('#password_confirmation').val()));
    });

    $('#result').html('Strength : Requires strong password.');

    /**
     * Check confirmation for match.
     *
     * @param password
     * @param password_confirmation
     *
     * @returns {string}
     */
    function checkMatch(password, password_confirmation) {

        if (password === password_confirmation) {

            return 'Match';

        } else {

            return 'Does Not Match';
        }
    }

    /**
     * Check the password strength.
     *
     * @param password
     * @returns {string}
     */
    function checkStrength(password) {

        var strength = 0;
        var message = 'Password is strong.';
        var password_length = '8';

        if (password.length < password_length) {

            return 'Too Short : Requires '+password_length+' or more characters.';
        }

        if (password.length >= password_length) {
            strength += 1;
        }

        if (password.match(/([a-z].*[A-Z])|([A-Z].*[a-z])/)) {
            strength += 1;
        } else {
            message = "Requires upper and lower case.";
        }

        if (password.match(/([a-zA-Z])/) && password.match(/([0-9])/)) {
            strength += 1;
        } else {
            message = "Requires letters and numbers.";
        }

        if (password.match(/([!,%,&,@,#,$,^,*,?,_,~])/)) {
            strength += 1;
        } else {
            message = "Requires Symbols (@, #, $, %, etc.).";
        }
        
        if (strength < 3) {
            return 'Weak : ' + message;
        } else if (strength == 3) {
            return 'Moderate : ' + message;
        } else {
            return 'Acceptable : ' + message;
        }
        
    }
});