The Royal Danish Navy ranks follows the NATO system of ranks and insignia, as does the rest of the Danish Defence. Outside this ranking system there are physicians (who may wear the same insignia in the Army/Air Force but with a slight variation in the Navy), nurses and veterinarians, while priests and judicial personnel wear completely different insignia and are without rank.
Besides the NATO-system, the Danish defence utilizes its own system, which for the navy is as follows:
The highest officer's rank is OF-9 (Admiral) which is reserved for the Chief of Defence (only when this seat is occupied by a naval officer) and the King of Denmark. The Prince Consort of Denmark held the rank of Admiral (ÃÂ la suite). Similarly, OF-8 (Vice-admiral) is reserved for the Vice Chief of Defence). OF-7 (Kontreadmiral) is used by the Chief of the Royal Danish Navy and OF-6 (Flotilleadmiral) by the chief of Danish Task Group as well as keepers of high-office positions. OF-4 and OF-5 are mainly chiefs of squadrons, schools and larger vessels. OF-1 through OF-3 are used in a variety of positions.
The Danish OR's also follow the NATO system, though there are no OR-6's. OR-4 (Korporal) is the highest of the M100-level ranks is and not considered a NCO-rank.
The branch of service emblems are worn by all NCOs and enlisted, except for who wears a crown.
The sleeve insignia was first introduced in the Royal Navy in 1871 and was based around the British Royal Navy. In order to become more standard, the admiral ranks were changed in 1951.