In this article, we will see how to check whether a number is a float or an integer in JavaScript. A float is a number with a decimal point, while an integer is a whole number or a natural number without having a decimal point.
Table of Content
We will explore every approach to Check if a Number is a Float or Integer, along with understanding their basic implementations.
Using the Number.isInteger() Method
The Number.isInteger() Method checks if the given number is an integer or not. It returns true if the number is an integer, and false if it’s a float or not a number at all.
Syntax
Number.isInteger(number);
Example: This example uses the Number.isInteger() Method to check the Number.
Javascript
const inputNumber = 42;const isInteger = Number.isInteger(inputNumber);console.log( `Is ${inputNumber} an integer? ${isInteger}`); |
Is 42 an integer? true
Using the Modulus Operator (%)
The Modulus Operator calculates the remainder when the number is divided by 1. If the remainder is 0, the number is an integer; otherwise, it’s a float.
Syntax
(number % 1 === 0);
Example: This example uses the Modulus Operator (%) to check the Number.
Javascript
const inputNumber = 3.14;const isInteger = inputNumber % 1 === 0;console.log( `Is ${inputNumber} a integer? ${isInteger}`); |
Is 3.14 a integer? false
Using Regular Expressions
This approach involves converting the number to a string and using a Regular Expression to check if it contains a decimal point. If it does, it’s a float; otherwise, it’s an integer.
Syntax
/\d+\.\d+/.test(numberString);
Javascript
const inputNumber = 123.456;const numberString = inputNumber.toString();const isFloat = /\d+\.\d+/.test( numberString);console.log( `Is ${inputNumber} a float? ${isFloat}`); |
Is 123.456 a float? true
