JavaScript Number.isNaN() Method

In JavaScript NaN is stand for Not-a-Number. The Number.isNaN() method returns true if a value is NaN. This method checks whether the passed value is NaN and of type Number, ensuring accurate identification of invalid numeric values.

Syntax

Number.isNaN(value)

Parameters

• Value: It is the value that 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. 

Example 1: In This example the GFGFun() function initializes an empty string res. It then appends the result of the Number.isNaN(123) method call to res. Since 123 is a valid number, Number.isNaN() returns false.

function GFGFun() {
    let res = "";
    res = res + Number.isNaN(123);
    console.log(res);
}
GFGFun();

false

Example 2: In this example the GFGFun() function initializes an empty string res. It then appends the result of the expression Number.isNaN(0 / 0) to res. Since division by zero results in NaN, Number.isNaN() returns true.

function GFGFun() {
    let res = "";
    res = res + Number.isNaN(0 / 0);
    console.log(res);
}
GFGFun();

true

Example 3: In this example the function GFGFun() initializes an empty string res, then appends the result of Number.isNaN(321) to res. Since 321 is a valid number, Number.isNaN() returns false.

function GFGFun() {
    let res = "";
    res = res + Number.isNaN(321);
    console.log(res);
}
GFGFun();

false

We have a complete list of Javascript Number Object methods, to check those please go through this Javascript Number Complete reference article.

Supported Browsers:

• Google Chrome
• Edge 
• Firefox
• Opera
• Safari