A kibibyte (KiB), derived from kilo-binary-byte, is a unit of digital information storage equal to 1024 bytes. This is in contrast to a kilobyte, meaning 1000 bytes. The unit was established by the International Electrotechnical Commission in 1998 to differentiate units in base 10 from units in base 2. IEC formally added it to IEC 60027-2 which was later superseded by IEC 80000-13.

Examples

• A typical L1I$ and L1D$ is between 8 and 64 KiB. For example, AMD's K5 had 16 KiB L1 instruction cache and 8 KiB data cache.
• A typical L2$ is between 64 and 512 KiB. For example Intel's Haswell had 256 KiB of L2 cache.
• A 16-bit CPU cannot directly address more than 64 KiB.