1920–1942
| Grade 1 | Grade 2 | Grade 3 | Grade 4 | Grade 5 | Grade 6 | Grade 7 | |
|---|---|---|---|---|---|---|---|
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No Insignia |
| Master Sergeant | First Sergeant | Technical Sergeant | Staff Sergeant | Sergeant | Corporal | Private First Class/Specialist | Private/Specialist |
| M/Sgt. | 1st Sgt. | T/Sgt. | S/Sgt. | Sgt. | Cpl. | Pfc. | Pvt. |
1942–1948
| 1st Grade | 2nd Grade | 3rd Grade | 4th Grade | 5th Grade | 6th Grade | 7th Grade | ||||
|---|---|---|---|---|---|---|---|---|---|---|
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No Insignia |
| Master Sergeant | First Sergeant | Technical Sergeant | Staff Sergeant | Technician Third Grade | Sergeant | Technician Fourth Grade | Corporal | Technician Fifth Grade | Private First Class | Private |
| M/Sgt. | 1st Sgt. | T/Sgt. | S/Sgt. | T/3. | Sgt. | T/4. | Cpl. | T/5. | Pfc. | Pvt. |
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USA
Army & Air Force
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Various | |||||||||||||||||||||||
| General of the Armies | General of the Army | General | Lieutenant General | Major General | Brigadier General | Colonel | Lieutenant Colonel | Major | Captain | First Lieutenant | Second Lieutenant | Officer Candidate | Officer Cadet | ||||||||||||||||||||||
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USA
Navy
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Various | |||||||||||||||||||||||
| Admiral of the Navy | Fleet Admiral | Admiral | Vice Admiral | Rear Admiral | Commodore | Captain | Commander | Lieutenant Commander | Lieutenant | Lieutenant (junior grade) | Ensign | Midshipman/Officer Candidate | |||||||||||||||||||||||
These are all main ranks in the U.S. WW2 army however there are many specifications or special ranks not mentioned here. You can look these up with a simple google search. U.S. ranks are well documented.