Show how many characters remaining in a HTML text box using JavaScript

You can bind key press event with your input box and returning false if characters are more than 160 will solve the problem jsfiddle.

JavaScript:

$('textarea').keypress(function(){

    if(this.value.length > 160){
        return false;
    }

    $("#remainingC").html("Remaining characters : " + (160 - this.value.length));
});​

HTML

<textarea></textarea>​
<span id='remainingC'></span>

Dynamic HTML element functionThe code in here with a little bit of modification and simplification:

<input disabled  maxlength="3" size="3" value="10" id="counter">
<textarea onkeyup="textCounter(this,'counter',10);" id="message">
</textarea>
<script>
function textCounter(field,field2,maxlimit)
{
 var countfield = document.getElementById(field2);
 if ( field.value.length > maxlimit ) {
  field.value = field.value.substring( 0, maxlimit );
  return false;
 } else {
  countfield.value = maxlimit - field.value.length;
 }
}
</script>

Hope this helps!

tip:

When merging the codes with your page, make sure the HTML elements(textarea, input) are loaded first before the scripts (Javascript functions)

Included below is a simple working JS/HTML implementation which updates the remaining characters properly when the input has been deleted.

Bootstrap and JQuery are required for the layout and functionality to match. (Tested on JQuery 2.1.1 as per the included code snippet).

Make sure you include the JS code such that it is loaded after the HTML. Message me if you have any questions.

Le Code:

$(document).ready(function() {
  var len = 0;
  var maxchar = 200;

  $( '#my-input' ).keyup(function(){
    len = this.value.length
    if(len > maxchar){
        return false;
    }
    else if (len > 0) {
        $( "#remainingC" ).html( "Remaining characters: " +( maxchar - len ) );
    }
    else {
        $( "#remainingC" ).html( "Remaining characters: " +( maxchar ) );
    }
  })
});

<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>

<div class="row">
  <div class="col-sm-6 form-group">
    <label>Textarea</label>
    <textarea placeholder="Enter the textarea input here.. (limited to 200 characters)" rows="3" class="form-control" name="my-name" id="my-input" maxlength="200"></textarea><span id='remainingC'></span>
  </div>
</div> <!--row-->