Check If the Value is an Integer in JavaScript



In this article, you will learn how to check if the value is an integer in JavaScript.

The Number.isInteger() method

The Number.isInteger method is a method that determines whether the value passed as an argument is an integer.
This method returns true if the value is an integer, false otherwise.

The syntax is below.


Anything with 0 decimal places, such as “1.0”, is considered an integer and returns true.

Number.isInteger(1); //true 
Number.isInteger(1.0); //true
Number.isInteger(0.1); //false 
Number.isInteger("string"); //false

Sample Code

Below is a sample code that gets a value from the input tag and determines if it is an integer.

const input1 = document.getElementById('el');
  console.log('The value is an integer.');
  console.log('The value is not an integer.');