JavaScript

Bitwise Operators

In bitwise operators, the operands are interpreted as a set of 32 bits (zeros and ones - short examples given in table below), as opposed to decimal, hexadecimal, or octal numbers. Bitwise operators return standard JavaScript numerical values, however.

Decimal:	0	1	2	3	4	5	6	7	8	9	10
4-bit binary:	0000	0001	0010	0011	0100	0101	0110	0111	1000	1001	1010

With bitwise logical operators (&, |, ^), each operand is treated as a thirty-two-bit integer, and each bit in one operand is paired with the corresponding bit in the other. The operators are then applied to each pair of bits.

In the case of bitwise shift operators (<<, >>, >>>), the first operand is a quantity to be shifted, and the second specifies the number of bit positions by which the first operand is to be shifted. The operands are converted to thirty-two-bit integers for shifting, and the result is returned having the same type as the left operator.

Operator	Name	Description	Example	Result
a & b	Bitwise AND	Returns a 1 in each bit position for which the corresponding bits of both operands are ones.	10 & 6	2
a \| b	Bitwise OR	Returns a 1 in each bit position for which the corresponding bits of either or both operands are ones.	10 \| 6	14
a ^ b	Bitwise XOR	Returns a 1 in each bit position for which the corresponding bits of either but not both operands are ones.	10 ^ 6	12
~ a	Bitwise NOT	Inverts the bits of its operand.	~ 10	-11
a << b	Left shift	Shifts `a` in binary representation `b` bits to left, shifting in zeros from the right.	10 << 2	40
a >> b	Sign-propagating right shift	Shifts `a` in binary representation `b` bits to right, discarding bits shifted off. Copies of the leftmost bit are shifted in from the left.	7 >> 1 -7 >>1	3 -4
a >>> b	Zero-fill right shift	Shifts `a` in binary representation `b` bits to the right, discarding bits shifted off, and shifting in zeros from the left.	-7 >>>1	2147483644