Starts with the letter 'J'
- Jacks and Witches. Play this variant on 84 squares with special pieces and special squares! By Antoine Fourrière.
- Janus Chess. Play Janus Chess on Game Courier. Author: Fergus Duniho. Inventor: Werner Schoendorf.
- Janus Kamil Chess. A crossover between Janus Chess and Modern Kamil Chess. By Jörg Knappen.
- Jester Chess. Featuring pieces that mimic last piece moved, archers that can either capture OR move. quadrapawns, and murray lions. Author: Jeremy Gabriel Good. Inventor: Thomas Havel.
- Jetan. Play Edgar Rice Burrough's Martian Chess or Jetan! Author: James Killian Spratt and Tony Quintanilla. Inventor: Edgar Rice Burroughs.
- Jetan Jeddara. Large variant of Jetan. Author: Tony Quintanilla and James Killian Spratt. Inventor: James Killian Spratt.
- Jetan Sarang. Play this large variation of Jetan! Author: James Killian Spratt and Tony Quintanilla. Inventor: James Killian Spratt.
- Joe Joyce Hyperchess. Easy to play 3D Chess variant where pieces can act on small board or large board. Author: Jeremy Gabriel Good. Inventor: Joe Joyce.
- Judkin's Shogi. Modern small shogi variant preset. Author: Charles Daniel and Armin Liebhart. Inventor: ? Judkin.
- Jumping Chess. Pieces capture by jumping. Board has extra edge squares making it 10x10. By Peter Aronson.
- Jumping Knights Chess. Nightriders replace Knights and War Machines have also been added to Jumping Chess. By David Paulowich.
- Jungles and Mountains Chess. Bull-Dozers must clear through jungle brush and Engineers must make passages through mountains to free up piece movement. By Gary K. Gifford.
- Juxtaposition Chess. Normal moves, plus pawns switch places with stones; pieces switch places with flags. By Gary K. Gifford.
Total items listed: 13