KB
Abbreviation with 7 meanings
| Stands for | Kilobyte |
|---|---|
| Meanings | 7 |
| Categories | Units & Measurements, Technology & Computing, Science & Engineering, Law & Legal, Sports |
| Also written | kB, kb |
KB has seven meanings. The most common are Kilobyte (data unit) and Kilobit (data unit); it can also stand for Knowledge Base, Boltzmann constant, Kilobase, King's Bench and Kettlebell.
Meanings of KB at a glance
| # | KB stands for | Context |
|---|---|---|
| 1 | Kilobyte | Units & Measurements › Data Unit |
| 2 | Kilobit | Units & Measurements › Data Unit |
| 3 | Knowledge Base | Technology & Computing › Computer |
| 4 | Boltzmann constant | Science & Engineering › Physics |
| 5 | Kilobase | Science & Engineering › Genetics |
| 6 | King's Bench | Law & Legal › Court |
| 7 | Kettlebell | Sports › Fitness and Exercise |
1. Kilobyte
Units & Measurements · Data Unit Abbreviations
A unit of digital storage equal to 1,000 bytes in the SI sense or 1,024 bytes in traditional computing usage. Small documents, emails, icons and web scripts are measured in kilobytes; a page of plain text is about 2 to 4 KB.
Example: Keep each profile image under 200 KB so the page loads quickly on mobile.
The SI-correct symbol is kB with a lowercase k, but KB is far more common. Because computers count in powers of two, early programmers used kilobyte for 1,024 bytes, a 2.4 percent difference that led the IEC to define the kibibyte (KiB) in 1998. Windows File Explorer still reports sizes in KB meaning 1,024 bytes, while macOS has used 1,000 since 2009.
2. Kilobit (kb)
Units & Measurements · Data Unit Abbreviations
One thousand bits, used for low data rates and small quantities of data such as audio bitrates, modem speeds and IoT sensor messages. A 128 kb/s MP3 stream uses just under 1 megabyte per minute.
Example: The voice codec runs at 24 kb/s, so a one-minute call uses only about 180 kilobytes.
Kilobit uses the decimal SI prefix, although some older telecom and memory-chip contexts meant 1,024 bits; the binary unit is the kibibit (Kibit). Capitalization signals the unit: kb or Kb usually means kilobits, while KB or kB means kilobytes, eight times more. Careful writers spell out "kbit" when precision matters.
3. Knowledge Base
Technology & Computing · Computer Abbreviations
Collection of support articles; at Microsoft, KB numbers identify both help articles and the Windows updates they describe. IT staff quote these numbers when tracking patches, failed installs and known issues.
Example: KB5034441 kept failing with error 0x80070643 until we enlarged the recovery partition.
Microsoft has numbered its support articles for decades, and each monthly cumulative update gets its own KB number. Many companies call their self-service help centers knowledge bases, and ITIL treats one as a core service-management tool. In data sizes, KB means kilobyte, an unrelated abbreviation; context makes the meaning clear.
4. Boltzmann constant (kB)
Science & Engineering · Physics Abbreviations
Constant linking temperature to energy at the level of particles, exactly 1.380649 x 10^-23 joules per kelvin since 2019. It appears in the ideal gas law written for molecules, in the formula for entropy and in the thermal noise of electronic circuits.
Example: At room temperature the thermal energy kB T is about 25 millielectronvolts.
Named after Ludwig Boltzmann, whose entropy formula S = k log W is engraved on his tombstone in Vienna, although Max Planck first wrote the constant explicitly. Its fixed value now defines the kelvin. Usually written k with a subscript B; the gas constant R equals kB times the Avogadro constant.
5. Kilobase (kb)
Science & Engineering · Genetics Abbreviations
One thousand base pairs (or nucleotides), the usual unit for sizes of genes, plasmids and DNA fragments. A typical plasmid is 3-10 kb, and the average human gene spans tens of kilobases including introns.
Example: The insert is 2.4 kb, so the recombinant plasmid should be about 7.1 kb in total.
Also written kbp for kilobase pairs. Gel ladders mark fragment sizes in kb. Not to be confused with kB or KB for kilobyte, a unit of data, although genomics combines the two worlds when sequencing files run to gigabytes.
6. King's Bench
Law & Legal · Court Abbreviations
Division of the High Court of England and Wales that hears contract and tort claims, defamation, personal injury and judicial review, and the Law Reports series publishing its leading judgments. The name switches between King's Bench and Queen's Bench with the sex of the reigning monarch.
Example: The libel claim was issued in the KB Division and listed for a preliminary trial on meaning.
Since the accession of Charles III in September 2022 it has been the King's Bench Division, with neutral citations ending (KB). Reports from 1901 to 1952 appear in the KB series of the Law Reports, such as [1932] 1 KB. In computing, KB means kilobyte.
7. Kettlebell
Sports · Fitness and Exercise Abbreviations
Cast-iron weight shaped like a ball with a handle, used for swings, snatches, Turkish get-ups and carries. Kettlebells are traditionally sized in kilograms or the old Russian unit, the pood (16 kg).
Example: Finisher: 100 KB swings with a 24 kg bell, broken up as needed.
Kettlebell training has deep roots in Russia and was popularized in the West around 2000 by Pavel Tsatsouline. The kettlebell swing is a hip-hinge movement, not a squat. In computing KB means kilobyte.
Related abbreviations
More data unit abbreviations
- GB – Gigabyte
- Gbps – Gigabits per second
- GiB – Gibibyte
- GT/s – Gigatransfers per second
- kbps – Kilobits per second
- KiB – Kibibyte
- lpi – Lines per inch
- MB – Megabyte
See all 36 data unit abbreviations →
More computer abbreviations
- IS – Information systems
- IT – Information technology
- ITIL – Information Technology Infrastructure Library
- ITSM – IT service management
- Mac – Macintosh
- MBR – Master Boot Record
- MDM – Mobile device management
- MS-DOS – Microsoft Disk Operating System
See all 92 computer abbreviations →
This entry is for general education and is not legal advice. Abbreviation use varies between institutions; always confirm in context.