kibibyte

A kibibyte (KiB) is a unit of digital information equal to 1024 bytes. It belongs to the set of binary prefixes introduced to distinguish binary data sizes from decimal ones such as the kilobyte (kB), which is typically 1000 bytes.

Definition and multiples: 1 KiB = 2^10 bytes = 1024 bytes. Larger units continue as 1 MiB = 1024 KiB, 1 GiB = 1024 MiB, and so on.

History: In 1998 the International Electrotechnical Commission introduced the binary prefixes kibi-, mebi-, gibi-, tebi-, pebi-, and exbi- with abbreviations KiB, MiB, GiB, TiB, PiB, EiB, to reduce ambiguity between binary and decimal multiples.

Usage: Adoption has been uneven. Some software and hardware continue to use kilobyte (kB) to denote 1024 bytes, while others follow the IEC prefixes and display KiB for 1024-byte values. In storage marketing, decimal prefixes are common, e.g., a 1 TB drive being advertised as 1,000,000,000,000 bytes.

In practice, KiB and its relatives are most common in technical documentation and in contexts where precise binary sizes matter, whereas everyday consumer interfaces may still use KB, MB, or GB with ambiguous meaning.

See also: Kilobyte, mebibyte.