The
kilobit is a multiple of the unit
bitA bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...
for digital
informationInformation in its most restricted technical sense is a message or collection of messages that consists of an ordered sequence of symbols, or it is the meaning that can be interpreted from such a message or collection of messages. Information can be recorded or transmitted. It can be recorded as...
or
computer storageComputer data storage, often called storage or memory, refers to computer components and recording media that retain digital data. Data storage is one of the core functions and fundamental components of computers....
. The prefix kilo (symbol k) is defined in the
International System of UnitsThe International System of Units is the modern form of the metric system and is generally a system of units of measurement devised around seven base units and the convenience of the number ten. The older metric system included several groups of units...
(SI) as a multiplier of 10
3 (1 thousand), and therefore,
- 1 kilobit = = .
The kilobit has the unit symbol
kbit or
kb.
Using the common
byteThe byte is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this reason it is the basic addressable element in many computer...
size of 8 bits, 1 kbit is equal to 125
byteThe byte is a unit of digital information in computing and telecommunications that most commonly consists of eight bits. Historically, a byte was the number of bits used to encode a single character of text in a computer and for this reason it is the basic addressable element in many computer...
s.
The kilobit is closely related to the
kibibitThe kibibit is a multiple of the bit, a unit of digital information storage, prefixed by the standards-based multiplier kibi , a binary prefix meaning 210...
, a unit multiple derived from the
binary prefixIn computing, a binary prefix is a specifier or mnemonic that is prepended to the units of digital information, the bit and the byte, to indicate multiplication by a power of 2...
kibi (symbol Ki) of the same order of magnitude, which is equal to = , or approximately 2% larger than the kilobit. Despite the definitions of these new prefixes for binary-based quantities of storage by international standards organizations, memory semiconductor chips are still marketed using the metric prefix names to designate binary multiples.
The kilobit is most commonly used in the expression of
data ratesIn telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time....
of digital communication circuits as kilobits per second (kbit/s or kb/s), or abbreviated as
kbps, as in, for example,
a 56 kbps PSTN circuit, or
a 512 kbit/s broadbandThe term broadband refers to a telecommunications signal or device of greater bandwidth, in some sense, than another standard or usual signal or device . Different criteria for "broad" have been applied in different contexts and at different times...
Internet connection.
The unit symbol kb is typographically similar to unit symbols of the
kilobyteThe kilobyte is a multiple of the unit byte for digital information. Although the prefix kilo- means 1000, the term kilobyte and symbol KB have historically been used to refer to either 1024 bytes or 1000 bytes, dependent upon context, in the fields of computer science and information...
, i.e. kB, with an upper case B. The
International Electrotechnical CommissionThe International Electrotechnical Commission is a non-profit, non-governmental international standards organization that prepares and publishes International Standards for all electrical, electronic and related technologies – collectively known as "electrotechnology"...
(IEC) therefore recommends the symbol bit instead of b. The prefix kilo is often used in fields of computer science and information technology with a meaning of multiplication by 1024 instead of 1000, contrary to international standards, in conjunction with the base unit byte and bit, in which case it is often written with a capital letter K, e.g., Kbit and KB. The decimal SI definition, 1 kbit/s = 1000 bit/s, is used uniformly in the context of
telecommunication transmission speedsIn telecommunications and computing, bit rate is the number of bits that are conveyed or processed per unit of time....
.