Köf may refer to one of a series of small German locomotives or Kleinlokomotiven including:

The second series of locomotives (EF66-100) are fundamentally the same design as the first, but with slightly more modern external styling.

The first series of locomotives, introduced from 1974, were built with curved front windscreens which would be later replaced by cheaper and sturdier flat ones.

The second series of locomotives have an improved driver's chair, which has been retrofitted on the older trains.

The DSB class ME are a series of diesel-electric locomotives, introduced in 1981.

From 1945 until the end of steam traction operation, the Ty2 was the largest series of locomotives in Poland.

Fairbanks-Morse, after producing a series of innovative locomotives that sold poorly, left the locomotive field (the company remains in business, in its original markets).

Korail Class 8000 is a series of South Korean electric locomotives operated by Korail.

WAG is a code given by Indian Railways to a series of electric locomotives, run in India.