What is the rank of an O-4 officer?

An O-4 officer is identified as a Major in the U.S. Army. This rank is part of the officer ranks, where O-1 to O-10 represent various levels of commissioned officers. The ranks are structured in a hierarchy, with O-1 being Second Lieutenant and O-10 being General.

In this ranking system, an O-4 specifically corresponds to Major, which is a field-grade officer rank above Captain (O-3) and below Lieutenant Colonel (O-5). Majors typically have significant responsibilities, often serving as staff officers in key operational roles or in leadership positions within a company or battalion.

Understanding the rank structure is essential for recognizing the roles and responsibilities associated with each level of command within the Army.