Kilobits to Bytes (kb to B)

1 kilobit equals 125 bytes exactly.

How to convert kilobits to bytes

To convert kilobits to bytes, multiply the number of kilobits by 125. This factor is exact. To go the other way, multiply bytes by 0.008.

bytes = kilobits × 125

Example: 10 kilobits = 1,250 bytes.

Decimal prefixes (kB, MB, GB) are powers of 1,000; binary prefixes (KiB, MiB, GiB) are powers of 1,024. Storage makers use decimal; Windows reports binary but labels it GB.

About these units

Kilobit (kb)

ComputingCurrent unit

1,000 bits (125 bytes). Used for data rates and sizes in telecommunications.

Kilobit means a thousand bits, and in telecommunications data rates are usually measured in decimal SI multiples. The article on the bit gives a handy example: a channel capacity of 8 kbit/s is 1 kB/s, so dividing kilobits by eight gives kilobytes. The binary counterpart, the kibibit, is 1,024 bits, but it is seldom used.

Symbols cause trouble. The IEC standard says to write kbit, while IEEE 1541-2002 recommends a lowercase b, giving kb, and the lowercase b may be confused with capital B for byte. On this site a kilobit is 125 bytes. The history behind it is that of the bit itself: Ralph Hartley proposed a logarithmic information measure in 1928, and Claude Shannon first used the word in 1948, crediting John W. Tukey.

1 kilobit = 125 bytes (exactly).

Sources: Wikipedia: Bit; Wikipedia: Kilobit

Byte (B)

ComputingCurrent unit

Eight bits. The basic addressable unit of memory and storage.

Werner Buchholz coined the word byte in June 1956 while working on the IBM Stretch computer; the earliest supporting document is dated 11 June 1956. He respelled bite on purpose, in his words to avoid accidental mutation to bit. At that stage a byte was any group of one to six bits, and a move to eight bits was considered in August 1956 and built into the design soon after. Louis Dooley later claimed he had coined the term around 1956 or 1957 on the SAGE project at MIT Lincoln Laboratory, where it meant groups of four bits, but Fred Brooks credited Buchholz.

IBM's System/360 adopted the eight-bit byte, and its success made that size the standard. The symbol is a capital B, and the unambiguous alternative is octet, a word used in protocol standards such as RFC 791. A byte can hold 256 distinct values, enough for a letter of the alphabet in a simple character set, which is why files and memory addresses are counted in bytes.

The byte is the reference unit for digital storage on this site.

Sources: Wikipedia: Byte; Wikipedia: Binary prefix

Related conversions

See all digital storage units.