How to Calculate if a Number is Odd or Even in JavaScript

Learn how to determine whether or not a number is odd or even in JavaScript.

I don't know how or why it took me so long to need this, but I only recently discovered the need to determine whether or not a number was even or odd. It uses the less-common remainder operator %.

Since all even numbers are divisible by 2 with no remainder, you can test whether a number is even with the following, where n is the number you'd like to test:

const isEven = (n) => (n % 2 === 0) ? true : false;

console.log( isEven(8) ) // output: true
console.log( isEven(9) ) // output: false

CodePen Example

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