AND(&) Bitwise Operator in JavaScript

JavaScript Bitwise AND(&) operator is used to compare two operands by performing an AND operation on the individual bits and returning 1 only if both the bits are one. The AND(&) Operator has a lot of real-world applications and the most famous one is to check whether a number is even or odd. The operation is represented by the “&” symbol

Let’s look at the truth table below to better understand the output of the AND operation between two bits.

A	B	OUTPUT ( A & B )
0	0	0
0	1	0
1	0	0
1	1	1

Syntax:

a & b

Example 1: In this example, we will understand the basics of AND operation

Javascript

let a = 5;
let b = 3;
console.log(a&b);

Output: 5 is represented as 101 and 3 is represented as 011. When the AND operation is performed 001 is returned which after conversion to decimal returns 1 only.

1

Example 2: In this example, we will use the Bitwise AND Operation to check if a number is odd or even.

Javascript

function checkOddOrEven(n) {
    if(n&1 == 1) {
        return "Number is odd";
    }
    return "Number is even";
}

console.log(checkOddOrEven(123));
console.log(checkOddOrEven(246));

Output: Odd numbers have 1 as the least significant bit whereas even numbers have 0 as the least significant bit so when AND operation is performed with 1, Odd numbers return 1 whereas even numbers return 0.

Number is odd
Number is even

Supported Browsers:

• Chrome
• Edge
• Firefox
• Opera
• Safari

We have a complete list of JavaScript Bitwise Operators, to check those please go through, the JavaScript Bitwise Operators article