# JavaScript isNaN Function Example with demo

Today, We want to share with you JavaScript isNaN Function Example.In this post we will show you Check if variable is a number in JavaScript, hear for isNaN function to check a number if string or not in JavaScript we will give you demo and example for implement.In this post, we will learn about Javascript Numbers, NaN, isNaN, parseInt, parsefloat function with an example.

## JavaScript isNaN Function Example

Contents

There are the Following The simple About JavaScript isNaN Function Example Full Information With Example and source code.

As I will cover this Post with live Working example to develop Data Type Conversion and IsNaN() Function in JavaScript, so the how to convert nan to number in javascript for this example is following below.

Simple Small JavaScript methods or function to check if a javascript variable is a number check.

```function check_live_Value(data_value){
if(isNaN(data_value)){
return false;
}else{
return true;
}
}
```

### Example : JavaScript Number isNaN() Method

```

JavaScript Number isNaN() Method.

Note: The Number.isNaN() function is not supported in IE 11 (and earlier versions).

function myFunction() {
var data_results = "";
data_results = data_results + Number.isNaN(123) + ": 123<hr>";
data_results = data_results + Number.isNaN(-1.23) + ": -1.23<hr>";
data_results = data_results + Number.isNaN(5-2) + ": 5-2<hr>";
data_results = data_results + Number.isNaN(0) + ": 0<hr>";
data_results = data_results + Number.isNaN('123') + ": '123'<hr>";
data_results = data_results + Number.isNaN('Hello') + ": 'Hello'<hr>";
data_results = data_results + Number.isNaN('2005/12/12') + ": '2005/12/12'<hr>";
data_results = data_results + Number.isNaN('') + ": ''<hr>";
data_results = data_results + Number.isNaN(true) + ": true<hr>";
data_results = data_results + Number.isNaN(undefined) + ": undefined<hr>";
data_results = data_results + Number.isNaN('NaN') + ": 'NaN'<hr>";
data_results = data_results + Number.isNaN(NaN) + ": NaN<hr>";
data_results = data_results + Number.isNaN(0 / 0) + ": 0 / 0<hr>";

document.getElementById("demo").innerHTML = data_results;
}

```