# How to Check Whether a Number is Decimal or Not in Javascript

In this tutorial, you will learn how to check whether a number is decimal or not in javascript. A number whose whole number part and fraction part is separated by decimal point is known as a decimal number. We have `float` primitive type to handle decimal numbers in javascript.

There are numerous ways to detect if a number is a decimal number or not, but I am going to share one of the simplest methods. This method involves the usage of the `parseFloat()` method and modulus operator (`%`).

The `parseFloat()` method will take a string as a parameter and return a floating-point number.  It may or may not have decimal because it depends if a string contains a whole number or decimal number. The modulus operator (`%`) returns the remainder of a division.

In the following example, we are going to enter a decimal number in the input field and use a combination of `parseFloat()` method and modulus operator (`%`) to detect whether the number is a decimal or not.  Depending upon the result, we will display a Boolean value on the screen.  Please have a look over the code example and steps given below.

HTML & CSS

• We have 4 elements in the HTML file and that includes `div`, `input`, `button`, and `h1` elements.
• The `div` element is just a wrapper for the rest of the elements.
• The inner text for the `button` element is `“Get”` and for the `h1` button, it is `“Result”`.
• We have done some basic styling using CSS and added the link to our `style.css` stylesheet inside the `head` element.
• We have also included our javascript file `script.js` with a `script` tag at the bottom.
```<!DOCTYPE html>
<html lang="en">
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<body>

<div>
<input type="number">
<button>Get</button>
<h1>Result</h1>
</div>
<script src="script.js"></script>
</body>
</html>```
```div {
text-align: center;
}

input, button {
display: inline-block;
}```

Javascript

• We have selected `button`, `input`, and `h1` elements using `document.querySelector()` and stored them in `btnGet`, `input`, and `result` variables respectively.
• We have attached the `click` event listener to the `button` element.
• In the event handler function, we are using the `parseFloat()` method and passing the value of the `input` element to convert the string to a decimal number. We are storing the returned value in the `num` variable.
• We have to divide `num` by 1 and get the remainder. To achieve that, we are using the modulus operator (`%`).  If the remainder is 0, that means the number is a whole number. Otherwise, it is a decimal number.  This calculation results in a Boolean value.
• We are displaying that Boolean value in the `h1` element.
```let btnGet = document.querySelector('button');
let input = document.querySelector('input');
let result = document.querySelector('h1');