How to calculate absolute value of number in JavaScript

You can calculate absolute value of a any number with the help of math.abs() method in JavaScript
You can use this methods as :
Math.abs(number)
where number is number for which the absolute value is needed.

see this :

<script type="text/javascript">
     document.write(Math.abs(23.7) + "<br />");
     document.write(Math.abs(-23.7) + "<br />");
     document.write(Math.abs(5-10));
     document.write(Math.abs(null) + "<br />");
</script>
 
The output  will be:
23.7
23.7
5
0

Example:

The following example create a form with two textbox and one button, when user click on button ‘txtResult’ shows absolute value according to enter number in ‘txtNumber’ number.

   <html>
    <body>
    <script language="JavaScript">
    	<!--
   	 function GetAbsolute()
	 {
       	    var number=document.form1.txtNumber.value;
            var absValue = Math.abs(number);
       	    document.form1.txtResult.value = absValue 
   	  }
        -->
    </script>
 
    <form name=form1>
    	 Enter Number:
   	 <input type="text" name="txtNumber" size=10>
   	  <br>
  	  Absolute Value:
   	 <input type="text" name="txtResult" size=10>
	  <br>
	 <input type="button" value="Find absolute" onClick='GetAbsolute()'>
    </form>
    </body>
 </html>