United States Army enlisted rank insignia of World War II

The U.S. Army enlisted rank insignia that was used during World War II differs from the current system. The color scheme used for the insignia's chevron design was defined as either silver grey on dark blue, olive drab on dark blue, or khaki on dark blue (as seen in the charts below). This scheme of rank insignia was established by War Department Circular No. 303 on 5 August 1920 and would see two significant changes in 1942. The usage of this style of insignia was ended by Department of the Army Circular No. 202, dated 7 July 1948, which provided for significant changes in both rank and insignia.

In 1920, the pay grade system was modified so the enlisted ranks were separated from the officer ranks. The "1st Grade" signified the highest enlisted grade (Master Sergeant) and "7th Grade" indicating the lowest (Private). In 1951, the pay grades were reversed with "1st Grade" being the lowest enlisted grade and "7th Grade" being the highest and an "E" prefix —which stands for "Enlisted"— was used to represent the enlisted pay grades.

The rank of Private Specialist, usually just called a Specialist, had the command responsibilities and official insignia of a Private First Class, but also conveyed higher pay depending on the specialty and skill. While the official insignia was just a single chevron, it was not uncommon for local commanders to authorize local use of specialist insignia which consisted of one chevron and one to six rockers depending on the pay grade of the specialist (one rocker at Grade 6, six rockers at Grade 1). To indicate their specialty, a trade badge was sometimes inset between the chevron and the first rocker. These were often identical to the abandoned trade badges used before the reforms of 1920.

Technical sergeant was renamed Sergeant First Class in 1948. However, it still survives as an Air Force rank.

A technical sergeant was often designated a platoon sergeant, acting as second-in-command.

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