J3
- 3J (disambiguation)
- County Route J3 (California)
- Eupheme (moon)
- Frozen orbit
- HMAS J3
- IATA
- Ishikawajima-Harima J3
- J class blimp
- J3 League
- J3 Operations Directorate
- J3 battlecruiser
- JAC J3
- Jalan Datin Halimah
- Janko group J3
- Junkers J 3
- Junsen type submarine
- Kempas Highway
- LNER Class J3
- Northwestern Air
- Piper J-3
- Samsung Galaxy J3
- Triangular cupola