Gigabyte (GB) to Gibibyte (GiB) and Megabyte (MB) to Mibibyte (MiB)
Converter

Enter a number in either field, then click outside of the text box. 

GB:   (x 109 bytes)
MB:   (x 106 bytes)
GiB:  (x 230 bytes)
MiB:  (x 220 bytes)


Gibibyte (GiB) is one of the standard units used in the field of data processing and data transmission (along with mebibyte (MiB), kibibyte (KiB), etc.). Gibibyte, mebibyte, and kibibyte are defined as powers of 2. 1 GiB equals 230 bytes or 1,073,741,824 bytes. Gibibyte is closely related to gigabyte (GB), which can be a synonym of gibibyte or can refer to 109 bytes or 1,000,000,000 bytes in accordance with International System of Units (SI).

Gigabyte (GB) can have different meanings in different contexts. When referring to computer memory, gigabyte is allways a “power of two” - 1,073,741,824 bytes, but when measuring hard drive capacity it is often defined as 1,000,000,000 bytes. Generally, operating systems calculate disk and file sizes using binary numbers, so a new 500 GB drive you've just purchased would be reported by the OS as "465.66 GB" (meaning 465.66 GiB).

Examples and comparisons with SI prefixes
one mebibyte 1 MiB = 220 B = 1,048,576 B
one megabyte 1 MB = 106 B = 1,000,000 B
one gibibyte 1 GiB = 230 B = 1,073,741,824 B
one gigabyte 1 GB = 109 B = 1,000,000,000 B

See also
Wikipedia “Gigabyte” article - http://en.wikipedia.org/wiki/Gigabyte
Prefixes for binary multiples - http://physics.nist.gov/cuu/Units/binary.html