JavaScript Bitwise Operators

Bitwise operators work on the binary (0s and 1s) representation of numbers. They are used less often than arithmetic or logical operators but are useful for low-level programming, performance tricks, or handling flags.

1. AND (&)

Performs an AND operation on each bit.

let a = 5;  // 0101 in binary
let b = 3;  // 0011 in binary
console.log(a & b); // 1 (0001 in binary)

2. OR (|)

Performs an OR operation on each bit.

let a = 5;  // 0101
let b = 3;  // 0011
console.log(a | b); // 7 (0111)

3. XOR (^)

Performs an exclusive OR operation (true if bits are different).

let a = 5;  // 0101
let b = 3;  // 0011
console.log(a ^ b); // 6 (0110)

4. NOT (~)

Flips all bits (0 → 1, 1 → 0).

let a = 5;  // 0101
console.log(~a);  // -6 (two’s complement)

5. Left Shift (<<)

Shifts bits to the left, adding 0s on the right.

let a = 5;  // 0101
console.log(a << 1);  // 10 (1010)

6. Right Shift (>>)

Shifts bits to the right, keeping the sign.

let a = 5;  // 0101
console.log(a >> 1);  // 2 (0010)

7. Zero-fill Right Shift (>>>)

Shifts bits to the right and fills with 0s, ignoring the sign.

let a = -5;
console.log(a >>> 1); // 2147483645