KM, Km, or km may stand for:

Science, computing, mathematics
  • Kilometre (km)
  • Kernel methods, computer science algorithms
  • Km, an electric Motor constant
  • KM programming language, programming language
  • Kelley-Morse set theory, a mathematics set theory
  • KM, the Michaelis constant in Michaelis–Menten kinetics
  • KM former stock symbol for Kmart
  • Kamenz (district), Germany (license plate indication)
  • Messenia, Greece (license plate indication)
  • .km, Internet top-level domain (ccTLD) for Comoros (ISO 3166-1 alpha-2 country code)
  • Konica Minolta, a manufacturer of electronics
  • Kia Motors, an automobile manufacturer
  • Air Malta (IATA code)
  • The KM Group, a multimedia group based in Kent
  • Knight of Malta (disambiguation), Christian order of knighthood
  • Kriegsmarine, the name of the German navy during the Nazi regime
  • Klubbmästeri, a type of Swedish student organisation
  • Kennis Music, a record label
  • Krav Maga, a self-defence and hand-to-hand combat system
  • The Ekranoplan given the name "Caspian Sea Monster" by U.S. intelligence operatives.
  • Krause-Mishler numbers, catalogue number references for the Standard Catalog of World Coins by Krause Publications
  • km, ISO 639 alpha-2 code for the Khmer language
  • Kinemantra Meditation, a meditation technique
  • Knowledge Management comprises a range of practices used by organisations to identify, create, represent, and distribute knowledge for reuse, awareness and learning
  • KM, Bosnia and Herzegovina konvertibilna marka, currency of Bosnia and Herzegovina