Show how many characters are remaining to enter in textbox or textarea using javascript

Show how many characters remaining in a html text box using javascript:
                                                                                     The following  javascript will help you to show how many characters are remaining for a textbox or textarea, The label placed next to the text box shown the number of character remaining.

<script type="text/javascript">
function txtCounters(id,max_length,myelement)
{
counter = document.getElementById(id);
field = document.getElementById(myelement).value;
field_length = field.length;
 if (field_length <= max_length)  {
//Calculate remaining characters
 remaining_characters = max_length-field_length;
//Update the counter on the page
  counter.innerHTML = remaining_characters;  }
 } </script>

<label for="txtName">Enter Your Text : </label>
<input type="text" id="txtName" size="50" maxlength="50" onkeyup="javascript:txtCounters('txtCounter',50,'txtName')"> <div id="txtCounter"><b>50</b></div>characters remaining.

Demo:

Enter Your Text :

50

characters remaining.