KiB

KiB, or kibibyte, is a unit of data size equal to 2^10 bytes, or 1024 bytes. It belongs to the binary prefixes defined by the International Electrotechnical Commission (IEC) to clearly indicate powers of 1024 rather than powers of 1000.

These prefixes include KiB, MiB, GiB, TiB, PiB, EiB, ZiB, and YiB, with corresponding names kibibyte, mebibyte, gibibyte, and so on. The decimal prefixes kilo- and mega- (kB, MB, GB) refer to 1000-based powers. To reduce ambiguity, the IEC established the separate kibi- system for binary units.

KiB is commonly used in computing for memory sizes, buffers, and file sizes that are based on powers of two. In practice, software and hardware labeling varies, and some contexts still use the traditional kilobyte to mean 1024 bytes.

Examples: 1 KiB = 1024 bytes; 1 MiB = 1024 KiB; 1 GiB = 1024 MiB. A 500 GB drive marketed in decimal contains 500,000,000,000 bytes, which is about 465.66 GiB in binary terms. This illustrates how decimal and binary labeling can yield different apparent sizes when comparing drives and memory.

Overall, KiB provides a precise, standardized way to refer to sizes that are powers of two, distinct from the decimal kilobyte used in SI.