In JavaScript, numbers are stored as 64-bit floating points. Bitwise operators in JavaScript operate on 32-bit operands.
Before performing a bitwise operation, JavaScript converts 64-bit floating point numbers into 32-bit signed integers, it then converts the result back to 64-bit numbers.
Examples of bitwise operators in JavaScript
| Operator | Name | Description |
| & | AND | returns 1 if both bits are 1 |
| OR | ||
| ^ | XOR | returns 1 if only one of the two bits is 1 |
| ~ | NOT | Inverts all the bits (1 becomes 0, and 0 becomes 1) |
| << | Zero-fill left shift | Shifts left by pushing zeros in from the right and letting the leftmost bits fall off |
| >> | Signed right shift | Shift right by pushing copies of the leftmost bit in from the left, and let the rightmost bits fall off |
| >>> | Zero-fill right shift | Shifts right by pushing zeros in from the left, and let the rightmost bits fall off |
Note: The maximum integer that is representable through a 32-bit signed number is 2147483647 and the minimum is -2147483648
JavaScript Bitwise AND (&)
When the JavaScript Bitwise AND operation is performed on a pair of bits, it returns 1 if both bits are 1 otherwise it returns 0.
| Operand 1 | Operand 2 | Bitwise AND operation |
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
The example below shows the working of the bitwise AND operation between two integers 10 and 6
// From decimal to binary
10 = 00001010
6 = 00000110
// Bitwise AND operation of 10 and 6
00001010
& 00000110
--------
00000010 = 2 (In decimal)
Example of JavaScript Bitwise AND operation
let x = 10;
let y = 6;
let result = x & y;
console.log(result); // 2
JavaScript Bitwise OR (|)
When the JavaScript Bitwise OR operation is performed on a pair of bits, it returns 1 if one of the bits is 1 otherwise it returns 0
| Operand 1 | Operand 2 | Bitwise OR Operation |
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 1 |
The example below shows the working of the bitwise OR operation between two integers 10 and 6
// From decimal to binary
10 = 00001010
6 = 00000110
// Bitwise OR operation of 10 and 6
00001010
| 00000110
--------
00001110 = 14 (In decimal)
Example of JavaScript Bitwise OR operation
let x = 10;
let y = 6;
let result = x | y;
console.log(result); // 14
JavaScript Bitwise XOR (^)
When the JavaScript Bitwise XOR operation is performed on a pair of bits, it returns 1 if the corresponding bits are different and returns 0 if they are the same.
| Operand 1 | Operand 2 | Bitwise XOR |
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
The example below shows the working of the bitwise XOR operation between two integers 10 and 6
// From decimal to binary
10 = 00001010
6 = 00000110
// Bitwise XOR operation of 10 and 6
00001010
^ 00000110
--------
00001100 = 12 (In decimal)
Example of JavaScript Bitwise XOR operation
let x = 10;
let y = 6;
let result = x ^ y;
console.log(result); // 12
Bitwise NOT (~)
The JavaScript Bitwise NOT operator flips the bit (if the bit is 1 it becomes 0, and if the bit is 0, it becomes 1).
The example below shows the working of bitwise NOT operation on 6
// From decimal to binary
6 = 00000000000000000000000000000110
// Bitwise NOT operation of 6
~ 00000000000000000000000000000110
--------------------------------
11111111111111111111111111111001 = -7 (In decimal)
The example below performs a JavaScript Bitwise NOT operation on 6
let x = 6;
let result = ~x;
console.log(result); // -7
Bitwise Zero Fill Left Shift <<
The bitwise zero fill left shift operation push in one or more zero bits from the right and the leftmost bits fall off. The operand before the << operator specifies the number to be shifted, and the operand after the << operator specifies the number of times to shift (number of 0 to be added).
The example below shows the working of bitwise zero fill left shift operation of 10 << 2
// From decimal to binary
10 = 00000000000000000000000000001010
// Bitwise Left Shift operation of 10 << 2
<< 00000000000000000000000000101000 = 40 (In decimal)
The example below performs a JavaScript Bitwise Left Shift operation on 10 and 2
let result = 10 << 2;
console.log(result); // 40
Bitwise Sign Preserving Right Shift >>
The bitwise sign preserving right shift operation push in copies of the leftmost bits from the left and the rightmost bits fall off. The operand before the >> operator, specify the number to be shifted, and the operand after the >> operator specifies the number of times to shift.
The example below shows the working of the bitwise Sign Preserving Right Shift operation of -10 >> 2
// From decimal to binary
-10 = 11111111111111111111111111110110
// Bitwise Sign Preserving Right Shift operation of -10 << 2
<< 11111111111111111111111111111101 = -3 (In decimal)
The example below performs a JavaScript Bitwise Sign Preserving Right Shift operation on -10 and 2
let result = -10 >> 2;
console.log(result); // -3
Bitwise Zero Fill Right Shift >>>
The bitwise zero-fill right shift operation push in one or more zero bits from the left and the rightmost bits fall off. The operand before the >>> operator specifies the number to be shifted, and the operand after the >>> operator specifies the number of times to shift (number of 0 to be added).
The example below shows the working of the bitwise Zero Fill Right Shift operation of 10 >>> 2
// From decimal to binary
10 = 00000000000000000000000000001010
// Bitwise Left Shift operation of 10 >>> 2
<<< 00000000000000000000000000000010 = 2 (In decimal)
The example below performs a JavaScript Bitwise Zero Fill Right Shift operation on 10 and 2
let result = 10 >>> 2;
console.log(result); // 2