isNAN() function in JavaScript

HTMLJavascriptProgramming Scripts

The isNaN() function accepts a value and determines whether the given value is a number or not.If so, this method returns true else it returns false. You can also call this method using Number object.

Syntax

Its Syntax is as follows

isNAN(5655);

Example

 Live Demo

<html>
<head>
   <title>JavaScript Example</title>
</head>
<body>
   <script type="text/javascript">
      var result1 = parseFloat("Ef00A.D3");
      document.write(isNaN(result1));
      document.write('<br>');
      var result2 = Math.log("welcome");
      document.write(isNaN(result2));
      document.write('<br>');
      var result3 = Math.log(1254);
      document.write(isNaN(result3));
   </script>
</body>
</html>

Output

true
true
false
raja
Published on 30-Oct-2018 07:23:08
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