Ranks of the Imperial Japanese Navy
The following graphs present the rank insignia of the Imperial Japanese Navy from its establishment in 1868 to its defeat during World War II in 1945. These designs were used from 1931 onwards.
Commissioned officer ranks
Cap badges:All commissioned officer rank names were the same as their army counterparts. The navy would prefix the common rank names with "Kaigun", while the army would prefix them with "Rikugun", meaning "Navy" and "Army", respectively. There was a minor difference in pronunciation of character 大 for Navy Lieutenant and Navy Captain. The navy pronounced it as "Dai", while the army pronounced it as "Tai". See the table below for details:
| All-forces ranks | English translation | IJN insignia | IJN insignia |
| Gensui | Grand Admiral | ||
| 海軍大将 | Admiral | ||
| 海軍中将 | Vice-admiral | ||
| 海軍少将 | Rear-admiral | ||
| 海軍大佐 | Captain | ||
| 海軍中佐 | Commander | ||
| 海軍少佐 | Lieutenant-commander | ||
| 海軍大尉 | Lieutenant | ||
| 海軍中尉 | Sub-lieutenant | ||
| 海軍少尉 | Ensign |
Cadet and warrant officer ranks
Enlisted rates
For seamen and petty officers, which were selected from enlisted men or conscripts and given one year of training in the Navy PO Academy, the names were different from the army names but were equal in rank. Different service branches within the navy had their specialization augment the common rank name. For example, Imperial Japanese Navy Air Service had "Flight" incorporated into the common rank name, such as Flight Petty Officer First Class or Flight Seaman Second Class. For practical use, these rank names were often shortened to 一飛曹 or 二飛, respectively. The enlisted rank insignia and names were updated on 1 November 1942. See the table below for details:Service branch colors
The branch of the Navy in which non-executive personnel served was indicated by a color code. For officers, including midshipmen, it was the color of cloth placed as background to the cuff stripes, on both sides of the gold lace on the shoulder boards, and as longitudinal piping on the collar patches. Midshipmen and cadets wore a colored anchor on the cap, which cadets wore on the shoulder boards as well. The branch of enlisted men was denoted by the color of the Chrysanthemum flower on their rank patch; line personnel using the default gold.| Color | Branch |
| Violet | Engineering |
| Brown | Ship and engine construction |
| Purple-brown | Ordnance construction |
| Red | Medical |
| Pale green | Legal |
| White | Paymaster |
| Black | Survey officers |
| Light blue | Aviation and Hydrography |
| Green | Chief carpenters |
| Grey-blue | Band master |