In this article I will explain with an example, how to show number of characters remaining in TextArea using JavaScript and jQuery.
HTML TextArea control does not have MaxLength property like the normal TextBox and Password fields have. Hence I have built a MaxLength jQuery plugin which simulates the working of the normal MaxLength with the help of JavaScript and jQuery.
HTML Markup
The HTML Markup consists of three HTML TextArea controls for which the Maximum Length validation will be implemented.
There is also an HTML DIV for displaying the Character Count for the second TextArea.
<textarea id="TextBox1" style="height: 100px; width: 300px"></textarea>
<br />
<br />
<div id="counter"></div>
<textarea id="TextBox2" style="height: 100px; width: 300px">Mudassar Khan</textarea>
<br />
<br />
<textarea id="TextBox3" style="height: 100px; width: 300px"></textarea>
Show number of characters remaining in TextArea using JavaScript and jQuery
The jQuery MaxLength plugin has the following required and optional parameters:
1. MaxLength (required) – Integer value indicating the Maximum character length limit.
2. CharacterCountControl (optional) – By default the plugin will display character count below the TextArea, but user has option to explicitly specify the Character Count Control.
Note: The character count control can only HTML SPAN or DIV.
3. DisplayCharacterCount (optional) – Default true. If set to false the Character counting will be disabled.
Inside the jQuery document ready event handler, the MaxLength jQuery plugin is applied to all the three HTML TextArea controls with three different configurations.
First TextArea – Default configuration. Maximum Length validation will be performed and Character count will be displayed.
Second TextArea – Maximum Length validation will be performed and Character Count will be displayed in a HTML DIV.
Third TextArea – Only Maximum Length validation will be performed.
<script type="text/javascript" src=""></script>
<script type="text/javascript" src="MaxLength.min.js"></script>
<script type="text/javascript">
    $(function () {
        //Normal Configuration
        $("[id*=TextBox1]").MaxLength({ MaxLength: 10 });
        //Specifying the Character Count control explicitly
            MaxLength: 15,
            CharacterCountControl: $('#counter')
        //Disable Character Count
            MaxLength: 20,
            DisplayCharacterCount: false
Show number of characters remaining in TextArea in real time using JavaScript and jQuery
Browser Compatibility

The above code has been tested in the following browsers.

Internet Explorer  FireFox  Chrome  Safari  Opera 

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