J class

The term J class may refer to:

Locomotives

• NZR J class (1874), steam locomotives operating in New Zealand from 1874 until 1935
• NZR J class (1939), steam locomotives operating in New Zealand from 1939
• WAGR J class, steam locomotives operating in Western Australia from the 1890s
• WAGR J class (diesel), diesel locomotives operating in Western Australia from the 1960s
• Victorian Railways J class, branch line steam locomotives operating in Victoria, Australia from 1954 to 1972

Watercraft

• J-class yacht, a racing yacht design constructed for the America's Cup competition between 1931 and 1937
• J class destroyer, a class of British-built destroyers active from 1937 until 1949
• British J class submarine, a class of British-built submarines operated by the Royal Navy and Royal Australian Navy between 1916 and 1930

Other

• Class J, a fictional planet category from Star Trek, consisting of small gas giants