Ki or KI may refer to:
Music
Ki (album), a 2009 album by Devin Townsend Project
Ki, a 1979 album by Kitarō
"Ki", a song from the album Minecraft – Volume Beta by C418
Businesses and organizations
Adam Air (2002–2008), an Indonesian airline (IATA code KI)
Karolinska Institute, Swedish university
Kativik Ilisarniliriniq, a school district in northern Quebec
Kenyon Institute, a British research institute in Jerusalem
Kiwanis International, service club
Klaksvíkar Ítróttarfelag, a Faroese semi-professional football club
Konservasi Indonesia, an Indonesian non-governmental conservation foundation
Language
Ki language, a Southern Bantoid language of Cameroon
Ki (kana), a Japanese syllabic character
Ki (cuneiform), a sign in cuneiform writing
Gikuyu language, ISO 639-1 code:ki
Names
Ki (Korean surname), a Korean surname
Ki or Qi (surname)
Ki or Ji (surname)
Places
Kangaroo Island, South Australia
Ki Monastery, in India
Kiawah Island, South Carolina, United States
King Island (Tasmania), Australia
Kings Island, Ohio, United States; an amusement park owned by Six Flags
Kiribati.ki, the ISO 3166-1 alpha-2 country code top level domain for Kiribati
Kitchenuhmaykoosib Inninuwug First Nation
Station code for Kurai Taji railway station, in Indonesia
Religion and metaphysics
Ki (goddess)
Qi, or ki in Japanese, a vital force according to Chinese culture that forms part of any living thing
Biology and chemistry
Ti (plant), also called Kī
Ki, an equilibrium constant for a chemical reaction or process "i":
dissociation constant applicable to process, abbreviated as "i".
a measure of the binding affinity of a ligand to a biomolecule
Potassium iodide, chemical formula KI
Gene knockin or Knock-in, a genetic engineering method
Ki Database, a database of biochemical information
Computing
Ki (prefix symbol), the prefix symbol of the binary unit prefix kibi
Ki, International Electrotechnical Commission standard symbol for number 1024
K-I algorithm, Kittler and Illingworth iterative algorithm for image segmentation thresholding
Ki (or Ki), the unique cryptographic key of each cell phone's SIM card
Electronics
Ki (standard), a wireless power transmission standard for kitched appliances from the Wireless Power Consortium
Other uses
Knowledge integration, in epistemology
Grover C. Winn (1886–1943), nicknamed "Ki", American lawyer and politician
Gakirah Barnes (died 2014), nicknamed "K.I" or "KI", American gangster
Kitchener line (KI) of the GO Transit rail network in Ontario, Canada