Officer Rank Notes: These ranks, and insignia, are taken from the discontinued Star Trek role playing game by FASA. These are not canon with the Star Trek series however it has been observed, in a number of episodes, that some Klingons were wearing these pins on their collars just as described in the FASA game. Whether or not they represent any rank is left up to your imagination. The only ranks ever mentioned in all of the series and movies were General, Fleet Admiral/Admiral, Brigadier, Captain, Commander Colonel, and Lieutenant. Sergeant and Bekk, although never mentioned by name, appear in the credits. The book 'Star Trek Klingon for the Galactic Traveler' lists those ranks plus Commodore, Ensign, and Yeoman. All ranks, when possible, are listed with their Klingon names and their Federation rank equivalents.

Klingon

Branch Notes: The Military Branch was never mentioned in Star Trek, these are directly from FASA's Star Trek game.

Until a person has obtained/made a uniform, they have the rank of Cadet if an officer, or Recruit if enlisted (both with no insignia). Once in uniform they are automatically promoted to rank of  Ensign if Navy or 2nd Lieutenant if Marine (if they become an officer) otherwise they are promoted to Lance Corporal (Marine enlisted only). There are no Navy Enlisted Ranks.