J1

J1, J01, J.I or J-1 may refer to:
* J-I, a Japanese launcher
* J1 type submarine, a WWII Imperial Japanese Navy cruiser submarines class
* J-1 visa, a type of U.S. visa for exchange visitors (e.g. students coming to the USA for an internship)
* J-1 World Heavyweight Championship, a wrestling competition
* AEG J.I, a World War I German ground attack aircraft
* Albatros J.I, a 1917 German ground-attack single-engine biplane aircraft
* ATC code J01, a section of the Anatomical Therapeutic Chemical Classification System
* DSER Class J1, a Dublin and South Eastern Railway
* Haplogroup J1 (Y-DNA), a Y-DNA haplogroup
* Janko group J1 in mathematics
* Junkers J 1, a 1916 German aircraft
* Junkers J.I, a 1917 German aircraft
* Lawrance J-1, a early 1920s engine used in American aircrafts
* LB&SCR J1 class, a British
* PRR J1, an American
* S/2003 J 1, a former name for Eukelade, a retrograde irregular satellite of Jupiter
* J1 Live Concert DVD, a DVD release by Chinese singer Jolin Tsai

and also :
* a shorthand for J. League Division 1 in Japanese Football
* J01 : acute sinusitis ICD-10 code