The period length of U.S. basic training varies depending on the branch of service. The Army has one week of indoctrination and nine weeks of basic training, followed by Advanced Individual Training. Navy basic training is eight weeks long, followed by intermediate and advanced training.
The Marine Corps basic training is 12 weeks longs, followed by infantry or combat training. Certain specialties then receive MOS training. Air Force basic training is six and half weeks long, followed by technical school for certain specialties. The Coast Guard basic training is eight weeks long, followed by Class A-School training. The Army National Guard has one week of indoctrination, followed by AIT training.