Ck1 or CK1 may refer to:
Transportation AIDC F-CK-1 Ching-kuo, the Taiwanese fighter jet the F-16 variant, see F-16 Fighting Falcon variants Chang Kong CK-1, the radio-controlled target drone Cicaré CK.1, the Argentine helicopter the locomotive, see CK class Cikunir 1 LRT station, a light rail station in Jakarta, Indonesia
Biochemistry Keratin 1 the cytokeratin, see Type II keratin Casein kinase 1, a family of protein kinases
Asteroids 1994 CK1, see 10146 Mukaitadashi 1993 CK1, see 20043 Ellenmacarthur 1989 CK1, see 4836 Medon 1986 CK1, see 3951 Zichichi 1983 CK1, see 4198 Panthera
Other Crusader Kings I, a grand strategy computer game by Paradox Interactive the illicit drug cocktail, see cocaine and ketamine the Calvin Klein product, see Calvin Klein (company) Pentecost biogeographic region, see Interim Biogeographic Regionalisation for Australia