Bitwise Operators
Bitwise operators in JavaScript operate on 32-bit operands. Internally, JavaScript converts 64-bit floating point numbers into 32-bit signed integers before performing the operation, it then converts back to 64-bit numbers to return the result.
JavaScript uses the following bitwise operators:
| Operator | Name | Description |
|---|---|---|
& |
AND | If both bits are 1, result is 1; otherwise 0. |
| |
OR | If either bit is 1, result is 1; otherwise 0. |
^ |
XOR | If bits are different, result is 1; otherwise 0. |
~ |
NOT | If bit is 0, result is 1; otherwise 0. |
<< |
Zero fill left shift | Pushes zeros in from right, leftmost bits fall off. |
>> |
Signed right shift | Pushes copies of leftmost bit in from left, rightmost bit falls off (preserves sign). |
>>> |
Zero fill right shift | Pushes zeros in from left, rightmost bits fall off. |
Examples
AND
console.log(19 & 7); // Output: 3// 10011 = 19// 00111 = 7// 00011 = 3
OR
console.log(19 | 7); // Output: 23// 10011 = 19// 00111 = 7// 10111 = 23
XOR
console.log(19 ^ 7); // Output: 20// 10011 = 19// 00111 = 7// 10100 = 20
NOT
Because integers are stored in two’s complement
(to change the sign, invert the binary digits and add one)
a ~ operation will change the sign of the number and change the absolute value by one.
console.log(~19); // Output: -20// 00000000000000000000000000010011 = 19// 11111111111111111111111111101100 = -20
Zero fill left shift
console.log(19 << 3); // Output: 152// 00000000000000000000000000010011 = 19// 00000000000000000000000010011000 = 152
Signed right shift
The >> operator preserves the sign of the operand by pushing copies of the leftmost bit in from the left.
console.log(19 >> 3); // Output: 2// 00000000000000000000000000010011 = 19// 00000000000000000000000000000010 = 2console.log(-20 >> 3); // Output: -3// 11111111111111111111111111101100 = -20// 11111111111111111111111111111101 = -3
Zero fill right shift
The >>> operator does not preserve the sign. It pushes zeros in from the left, pushing the sign bit out of its leftmost position.
console.log(19 >>> 3); // Output: 2// 00000000000000000000000000010011 = 19// 00000000000000000000000000000010 = 2console.log(-20 >>> 3); // Output: 536870909// 11111111111111111111111111101100 = -20// 00011111111111111111111111111101 = 536870909
Codebyte Examples
Execute the following to illustrate the use of Bitwise & operator:
Execute the following to illustrate the use of Bitwise | operator:
Execute the following to illustrate the use of Bitwise ^ operator:
Execute the following to illustrate the use of Bitwise ~ operator:
Execute the following to illustrate the use of Bitwise << operator:
Execute the following to illustrate the use of Bitwise >> operator:
Execute the following to illustrate the use of Bitwise >>> operator:
Contribute to Docs
- Learn more about how to get involved.
- Edit this page on GitHub to fix an error or make an improvement.
- Submit feedback to let us know how we can improve Docs.
