JavaScript Number.isNaN() Method

Below is the example of the Number.isNaN() Method.

• Example:

  <script>
  function GFGFun() {
    var res = "";
    res = res + Number.isNaN(123);
  document.write(res);
  
  }
  GFGFun();
  </script>
• Output:

  false

The Number.isNan method in JavaScript is used to determines whether the passed value is NaN(Not a Number) and is of the type “Number”.
In JavaScript, the value NaN is considered a type of number.

Syntax:

Number.isNaN(value)

Parameters Used:
1. Value :It is the value which is to be tested for NaN.

Return Value:
The Number.isNaN() method in JavaScript returns true if the passed value is Nan and is of the type number,else it returns false.

Examples:

Input : 0/0
Output : true
     
Input : 213
Output : false

Input : '213'
Output : false

Input : 'hello'
Output : false

Input : NaN
Output : true

1. When an equation resulting in infinite value is passed as a parameter.

   <script>
   function GFGFun() {
     var res = "";
     res = res + Number.isNaN(0/0);
   document.write(res);
   
   }
   GFGFun();
   </script>

   Output:

   Output : true

2. When a number is passed as a parameter.

   <script>
   function GFGFun() {
     var res = "";
     res = res + Number.isNaN(321);
   document.write(res);
   
   }
   GFGFun();
   </script>

   Output:

   Output : false

3. When a number in string representation is passed as a parameter.

   <script>
   function GFGFun() {
     var res = "";
     res = res + Number.isNaN(213);
   document.write(res);
   
   }
   GFGFun();
   </script>

   Output:

   Output : false

4. When a string is passed as a parameter.

   <script>
   function GFGFun() {
     var res = "";
     res = res + Number.isNaN("hello");
   document.write(res);
   
   }
   GFGFun();
   </script>

   Output:

   Output : false

5. When Nan is passed as a parameter.

   <script>
   function GFGFun() {
     var res = "";
     res = res + Number.isNaN(NaN);
   document.write(res);
   
   }
   GFGFun();
   </script>

   Output:

   Output : true

Supported Browsers:

• Google Chrome 25 and above
• Firefox 15 and above
• Apple Safari 9 and above
• Opera 15 and above
• safari 9 and above