KF or Kf may refer to:
Businesses and brands KF Aerospace, a Canadian aerospace company KF Cargo, a Canadian cargo airline KF Defence Programs, a Canadian defense contractor Korea Foundation Air Belgium, an airline based in Belgium (IATA code KF) Blue1, a defunct airline based in Finland (IATA code KF) Kelly's Fuels, fuels merchant in Northern Ireland Kettle Foods, a snack foods manufacturer Kooperativa Förbundet, a cooperative Swedish retail chain KrisFlyer, the frequent flyer program of Singapore Airlines
Games Katamari Forever, a video game for the PlayStation 3 Killing Floor (2009 video game), a cooperative survival horror video game
Science and technology Chemistry Potassium fluoride, a chemical substance Cryoscopic constant, Kf, related to freezing-point depression Karl Fischer titration Stability constants of complexes, abbreviated as Kf (constant of formation)
Other uses in science and technology A member of the Mazda K engine family Kalman filter, in mathematics Kleinflansch, a quick release vacuum flange Filtration coefficient Kline–Fogleman airfoil KDE Frameworks, a collection of libraries for Qt applications
Sports Knattspyrnufélag Fjallabyggðar, an Icelandic sports team KF, in kart racing, the designation of Original Kart from 2013–2016
Other uses Kiwi Farms, a web forum