strength-meter

---

A dynamic strength meter for password input validation with various configurable options. The strength scoring calculation is inspired from password meter created by Jeff Todnem.

Features

1. Convert any password input to an advanced password strength validation plugin. Will fallback to a normal password input for browsers not supporting JQuery or Javascript.
2. The plugin will offer ability to toggle password mask (show/hide password text) and display a dynamic strength meter as you type. Uses advanced strength calculation algorithm which can be customized by setting/overriding the default validation rules.
3. The plugin automatically converts an input with type = password to the strength validation plugin if you set its class = strength. All options to the password input can be passed as HTML5 data attributes.
4. Configurable templates to control the style and display of the entire plugin. The password input and the various components of the strength meter can be customized. The default template uses styling compatible with Bootstrap 3.x & Bootstrap 4.x markup to display the password input, toggle, and strength meter.
5. Internationalization enabled to show messages in languages other than Englsh. At this stage translations are available for 4 languages (German, French, Italian, and Russian). The titles for verdicts and toggle mask can be configured.
6. Show and hide meter and/or toggle password mask
7. Reset plugin to the initial value when the form is reset.
8. Plugin events that traps the change, reset, and toggle of the input.
9. Plugin methods to refresh the input and strength with a custom value.
10. Plugin methods to return score and verdict.
11. Configurable strength verdicts classes and titles.

Demo

View the plugin documentation and plugin demos at Krajee JQuery plugins.

Latest Release

NOTE: The latest version of the plugin is v1.1.4. Refer the CHANGE LOG for details.

Pre-requisites

1. Latest JQuery
2. Most modern browsers supporting CSS3 & JQuery. For Internet Explorer, one must use IE versions 9 and above.
3. Bootstrap 4.x (or bootstrap 3.x) is supported by default for styling. But usage of this framework is optional. The plugin templates use the Bootstrap 3.x markup by default. So for the default markup to render correct, you would need Bootstrap 3.x CSS to view the styles properly. If you do not wish to use Bootstrap, you can easily override the templates with your markup and styles.

Installation

Using Bower

You can use the bower package manager to install. Run:

bower install strength-meter

Using Composer

You can use the composer package manager to install. Either run:

$ php composer.phar require kartik-v/strength-meter "dev-master"

or add:

"kartik-v/strength-meter": "dev-master"

to the require section of your composer.json file

Manual Install

You can also manually install the plugin easily to your project. Just download the source ZIP or TAR ball and extract the plugin assets (css and js folders) into your project.

Usage

Step 1: Load the following assets in your header.

<link href="http://netdna.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css" rel="stylesheet">
<link href="path/to/css/star-strength.min.css" media="all" rel="stylesheet" type="text/css" />
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.0/jquery.min.js"></script>
<script src="path/to/js/star-strength.min.js" type="text/javascript"></script>

If you noticed, you need to load the jquery.min.js and bootstrap.min.css in addition to the star-strength.min.css and star-strength.min.js.

Note: You can skip the bootstrap.min.css if you do not need Bootstrap 3.x styling. To use your own style, you need to setup the inputTemplate, meterTemplate, and mainTemplate options to match your CSS Styling needs.

In addition, you can load a locale specific script for your language specific translation. For example to load German translations:

<script src="path/to/js/locales/star-strength-de.js" type="text/javascript"></script>

Step 2: Initialize the plugin on your page. For example,

// initialize with defaults
$("#password-id").strength();

// with plugin options
$("#password-id").strength({showMeter: true, toggleMask: false});

The #password-id is the identifier for the password input (type=password) on your page.

Alternatively, you can directly call the plugin options by setting data attributes to your input field.

<input id="password-id" type="password" class="strength" data-toggle-title="Display Password" >

Documentation

Plugin Options

The plugin supports these following options:

language

string language configuration for the plugin to enable the plugin to display messages for your locale (you must set the ISO code for the language). This setting also allows you to have multiple language widgets on the same page. The locale JS file for the language code must be defined as mentioned in the translations section. The file must be loaded after strength-meter.js.

showMeter

boolean whether the strength meter is to be displayed. Defaults to true.

showToggle

boolean whether to display the checkbox for toggling display of password text. Defaults to true.

inputTemplate

string the template for displaying the password input field (when toggleMask is true). This defaults to:

<div class="input-group">
    {input}
    <span class="input-group-addon">{toggle}</span>
</div>

The following special variables will be replaced in the template:

• {input} will be replaced with the password input
• {toggle} will be replaced with the toggle mask checkbox.

inputNoToggleTemplate

string the template for displaying the password input field (when toggleMask is false). This defaults to:

{input}

The following special variables will be replaced in the template:

• {input} will be replaced with the password input.

meterTemplate

string the template for displaying the password strength meter. This defaults to:

<div class="kv-scorebar-border">
    {scorebar}
    {score}
</div>
{verdict}

The following special variables will be replaced in the template:

• {scorebar} will be replaced with the strength score color bar.
• {score} will be replaced with the strength score in %.
• {verdict} will be replaced with the calculated strength verdict.

mainTemplate

string the template for displaying the overall widget/plugin. This defaults to:

<table class="kv-container">
    <tr>
        <td>{input}</td>
        <td class="kv-meter-container">{meter}</td>
    </tr>
</table>

The following special variables will be replaced in the template:

• {input} will be replaced with the parsed output from the inputTemplate.
• {meter} will be replaced with the parsed output from the meterTemplate.

meterClass

string the CSS class for displaying the meter. Defaults to kv-meter.

scoreBarClass

string the CSS class for displaying the strength score color bar. Defaults to kv-scorebar.

scoreClass

string the CSS class for displaying the strength score. Defaults to kv-score.

verdictClass

string the CSS class for displaying the strength verdict. Defaults to kv-verdict.

containerClass

string the CSS class for wrapping the whole widget. Defaults to kv-password.

inputClass

string the CSS class for displaying the password input. Defaults to form-control.

toggleClass

string the CSS class for displaying the toggle mask checkbox. Defaults to kv-toggle.

toggleTitle

string the title to be displayed on hovering the toggle mask checkbox. Defaults to Show/Hide Password. If you load in a locale specific JS, this will be overridden with the language specific toggleTitle.

verdictTitles

array the verdict titles corresponding to each strength verdict (0 to 6). If you load in a locale specific JS, this will be overridden with the language specific verdict. Defaults to

{
    0: 'Too Short',
    1: 'Very Weak',
    2: 'Weak',
    3: 'Good',
    4: 'Strong',
    5: 'Very Strong',
}

verdictClasses

array the verdict CSS classes corresponding to each strength verdict (0 to 6). Defaults to

{
    0: 'label label-default',
    1: 'label label-danger',
    2: 'label label-warning',
    3: 'label label-info',
    4: 'label label-primary',
    5: 'label label-success',
}

rules

array the strength validation rules. You normally do not need to change this, as this will impact the strength score algorithm. Defaults to:

{
    midChar: 2,
    consecAlphaUC: 2,
    consecAlphaLC: 2,
    consecNumber: 2,
    seqAlpha: 3,
    seqNumber: 3,
    seqSymbol: 3,
    length: 4,
    number: 4,
    symbol: 6
}

Each rule element corresponds to the following:

• midChar: The multiplication factor (addition) for middle numbers or symbols.
• consecAlphaUC: The multiplication factor (reduction) for consecutive upper case alphabets.
• consecAlphaLC: The multiplication factor (reduction) for consecutive lower case alphabets.
• consecNumber: The multiplication factor (reduction) for consecutive numbers.
• seqAlpha: The multiplication factor (reduction) for sequential alphabets (3+).
• seqNumber: The multiplication factor (reduction) for sequential numbers (3+).
• seqSymbol: The multiplication factor (reduction) for sequential symbols (3+).
• length: The multiplication factor (addition) for the count of characters.
• number: The multiplication factor (addition) for count of numbers in the input.
• symbol: The multiplication factor (addition) for count of symbols in the input.

Plugin Events

The plugin supports these events:

strength.change

This event is triggered when the password input/strength is changed.

Example:

$('#input-id').on('strength.change', function(event) {
    console.log("strength.change");
});

strength.reset

This event is triggered when the password input/strength is reset to initial value.

Example:

$('#password-id').on('strength.reset', function(event) {
    console.log("strength.reset");
});

strength.toggle

This event is triggered on toggling the password toggle mask (i.e. when password is shown/hidden).

Example:

$('#password-id').on('strength.toggle', function(event) {
    console.log("strength.toggle");
});

Plugin Methods

The plugin supports these methods:

refresh

Refreshes the strength after changing the password input value via javascript.

$('#password-id').val(3);
$('#password-id').strength('refresh');

reset

Reset the strength to the score based on the initial value of the password. For example after a form reset.

$('#password-id').strength('reset');

score

Return the current strength score:

alert($('#password-id').strength('score'));

verdict

Return the current strength verdict index:

alert($('#password-id').strength('verdict'));

License

strength-meter is released under the BSD 3-Clause License. See the bundled LICENSE.md for details.