Kilobit

A kilobit is a unit of information, abbreviated kbit (or kb).

The standard definition is 1 kilobit = 10³ bit = 1,000 bit. In the context of storage-memory and address-space sizes, the alternative binary definition of 2¹⁰ = 1,024 bit is occasionally used (see Binary prefix), although this usage is ambiguous.

Kilobits are commonly used to express digital communication speeds, e.g. a 56 kbit/s PSTN or 512 kbit/s broadband Internet connection. In the context of telecommunication transmission speeds, the decimal definition 1 kilobit = 1,000 bit is used uniformly.

The kilobit is closely related to the kibibit, which is unambiguously equal to 2¹⁰ = 1,024 bit.

Kilobit (abbreviated to kb with a lower case b) is sometimes confused with the term kilobyte (abbreviated to kB or KB with an upper case B).

See also

• bit
• kibibit
• kilobyte
• kilobit per second
• binary prefix
• orders of magnitude (data)
• IEEE information for authors, page A1 & A4