The typical age range for joining the United States Army is 17 to 35, according to the Army's website. During times of war, or when the Army is low on service members and enlistees, the age limit is sometimes raised. During the Iraq War, for instance, the Army raised the age limit to 42.
Additional Army Qualifications
One of the reasons the standard age limit is 35 is that Army soldiers must meet rigid physical standards. New enlistees must be in good condition and take physical fitness tests that measure strength and endurance. You must also be a citizen or a legal permanent resident with a high school diploma, have good moral standing, and agree to a criminal background check.