Unsigned right shift (>>>)
The unsigned right shift operator (>>>
)
(zero-fill right shift) shifts the first operand the specified number of bits to the
right. Excess bits shifted off to the right are discarded. Zero bits are shifted in from
the left. The sign bit becomes 0
, so the result is always non-negative.
Unlike the other bitwise operators, zero-fill right shift returns an unsigned 32-bit
integer.
Syntax
a >>> b
Description
This operator shifts the first operand the specified number of bits to the right.
Excess bits shifted off to the right are discarded. Zero bits are shifted in from the
left. The sign bit becomes 0
, so the result is always non-negative. Unlike
the other bitwise operators, zero-fill right shift returns an unsigned 32-bit integer.
For non-negative numbers, zero-fill right shift and sign-propagating right shift yield
the same result. For example, 9 >>> 2
yields 2, the same as
9 >> 2
:
9 (base 10): 00000000000000000000000000001001 (base 2)
--------------------------------
9 >>> 2 (base 10): 00000000000000000000000000000010 (base 2) = 2 (base 10)
However, this is not the case for negative numbers. For example,
-9 >>> 2
yields 1073741821, which is different than
-9 >> 2
(which yields -3
):
-9 (base 10): 11111111111111111111111111110111 (base 2)
--------------------------------
-9 >>> 2 (base 10): 00111111111111111111111111111101 (base 2) = 1073741821 (base 10)
Examples
Using unsigned right shift
9 >>> 2; // 2
-9 >>> 2; // 1073741821
Specifications
Specification |
---|
ECMAScript Language Specification # sec-unsigned-right-shift-operator |
Browser compatibility
BCD tables only load in the browser