Number.isNaN() In JavaScript

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

When an equation resulting in infinite value is passed as a parameter.
<script type="text/javascript">

    var num=0/0;

         document.write("Output : " + num.isNaN());

      </script>
Output:
```
Output : true
```
When a number is passed as a parameter.
<script type="text/javascript">

    var num=213;

         document.write("Output : " + num.isNaN());

      </script>
Output:
```
Output : false
```
When a number in string representation is passed as a parameter.
<script type="text/javascript">

    var test='213';

         document.write("Output : " + test.isNaN());

      </script>
Output:
```
Output : false
```
When a string is passed as a parameter.
<script type="text/javascript">

    var test='hello';

         document.write("Output : " + test.isNaN());

      </script>
Output:
```
Output : false
```
When Nan is passed as a parameter.
<script type="text/javascript">

    var check=Nan;

         document.write("Output : " + check.isNaN());

      </script>
Output:
```
Output : true
```

My Personal Notes

Recommended Posts:

Shubrodeep Banerjee

I am a technology enthusiast who has a keen interest in programming I am pursuing Engineering in Computer Science from GEU, Dehradun I like to unwind by watching movies and English sitcomsI have a keen interest in music

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.