Breaking down the 24 ranks of the U.S. military

Active duty personnel (excluding Coast Guard): 46,806

Army: Private

Navy: Seaman Recruit

Air Force: Airman Basic

Marine Corps: Private

Coast Guard: Seaman Recruit

Across all branches of the military, recruits enter the service at the E-1 grade. Privates belong in the lowest enlisted rank, and they wear no insignia. They begin their basic training, where they learn the fundamentals of their branch, the code of conduct, and professional and physical standards they are expected to follow. They have no responsibility other than training and learning to follow orders.

Active duty personnel (excluding Coast Guard): 71,437

Army: Private

Navy: Seaman Apprentice

Air Force: Airman

Marine Corps: Private First Class

Coast Guard: Seaman Apprentice

In the Army, the rank of E-2 private is known as private second class to differentiate them from newly enlisted privates. However, they remain the most basic level of soldier. This holds true in other branches like the Navy, where there is little difference in the daily life of E-1 and E-2 enlisted personnel. One of the key differences across all branches is that advancement to the E-2 grade earns you an insignia on your uniform.  

Active duty personnel (excluding Coast Guard): 186,366

Army: Private First Class

Navy: Seaman

Air Force: Airman First Class

Marine Corps: Lance Corporal

Coast Guard: Seaman

A private first class is the highest-ranking private in the Army and is a member of the organization's most populous rank, where they're expected to master individual duties and begin preparing for supervisory responsibility upon graduating to the next grade. In the Marines and the Navy, the grade of E-3 represents the most senior of the junior enlisted classification, and it's where they'll begin competing for the rank of non-commissioned officer (NCO).

Active duty personnel (excluding Coast Guard): 255,718

Army: Corporal/Specialist

Navy: Petty Officer Third Class

Air Force: Senior Airman

Marine Corps: Corporal

Coast Guard: Petty Officer Third Class

In the Navy, Marines, and Coast Guard, the rank of E-4 represents a graduation from each branch's entry-level classification. In the Coast Guard, a seaman becomes a petty officer. In both the Navy and the Marines, junior enlisted personnel become NCOs. In the Army, there are two classifications associated with the grade of E-4. Specialists remain enlisted soldiers, but corporals are bumped up to the classification of NCO.

Active duty personnel (excluding Coast Guard): 213,867

Army: Sergeant

Navy: Petty Officer Second Class

Air Force: Staff Sergeant

Marine Corps: Sergeant

Coast Guard: Petty Officer Second Class

By the time they've reached the E-5 grade, all military personnel across all branches are no longer members of their organization's junior classification. They are now officers, and as such, they're expected to be proficient in their skills, lead, and set an example for junior enlisted members. At this rank, members of the Air Force move from enlisted airman to NCO. In the Marines and Army, they're sergeants who lead squads and teams.

Active duty personnel (excluding Coast Guard): 155,091

Army: Staff Sergeant

Navy: Petty Officer First Class

Air Force: Technical Sergeant

Marine Corps: Staff Sergeant

Coast Guard: Petty Officer First Class

In the Marines, E-6 represents a jump from NCO to staff NCO. They're now career Marines charged with running platoons of 40 to 50 people. In the Coast Guard, the grade of E-6 brings the power to act as law enforcement or a federal customs officer.

Active duty personnel (excluding Coast Guard): 88,472

Army: Sergeant First Class

Navy: Chief Petty Officer

Air Force: Master Sergeant

Marine Corps: Gunnery Sergeant

Coast Guard: Chief Petty Officer

In the Navy, E-7 represents a jump from NCO to senior NCO. More exceptional and experienced than standard chiefs, they have more responsibility and more clout. In the Coast Guard, the move to E-7 means a bump in classification from petty officer to chief petty officer.

Active duty personnel (excluding Coast Guard): 25,894

Army: First Sergeant/Master Sergeant

Navy: Senior Chief Petty Officer

Air Force: Senior Master Sergeant

Marine Corps: First Sergeant/Master Sergeant

Coast Guard: Senior Chief Petty Officer

In the Army, E-8 could be a master sergeant or a first sergeant, the latter of which generally requires more than 15 years of service and is recognized as the most tactically and technically proficient leader in a company. In the Marines, the dual ranks are the same, with first sergeants and master sergeants being equal in rank. However, first sergeants are responsible for personnel and master sergeants are technical managers.  

Active duty personnel (excluding Coast Guard): 9,880

Army: Sergeant Major

Navy: Master Chief Petty Officer

Air Force: Chief Master Sergeant

Marine Corps: Sergeant Major/Master Gunnery Sergeant

Coast Guard: Master Chief Petty Officer

There are three possible ranks at the E-9 pay grade, the most senior of which is the highest-ranking enlisted officer in the entire organization. This is true across all five branches: the Army, Navy, Air Force, Coast Guard, and Marines.  

Active duty personnel (excluding Coast Guard): 2,366

Army: Warrant Officer 1

Navy: —

Air Force: —

Marine Corps: Warrant Officer 1

Coast Guard: —

The Air Force doesn't have warrant officers and both the Navy and the Coast Guard have no W-1 grade. In both the Army and the Marines, however, the rank of Warrant Officer 1 means you're the most technically and tactically proficient at your given specialty—even beyond master gunnery sergeants in the Marines.  

Active duty personnel (excluding Coast Guard): 6,955

Army: Chief Warrant Officer 2

Navy: Chief Warrant Officer 2

Air Force: —

Marine Corps: Chief Warrant Officer 2

Coast Guard: Chief Warrant Officer 2

Unlike many other nations, warrant officers in the United States Armed Forces occupy a rank classification that's uniquely their own. They are senior to the all enlisted grades up to E-9, but subordinate to commissioned officers. In the Navy and Coast Guard, W-2 is the entry level grade for warrant officers.

Active duty personnel (excluding Coast Guard): 5,511

Army: Chief Warrant Officer 3

Navy: Chief Warrant Officer 3

Air Force: —

Marine Corps: Chief Warrant Officer 3

Coast Guard: Chief Warrant Officer 3

The rank of chief warrant officer 3 is reserved for those with even more expertise and experience than chief warrant officers. In the Army, they can serve with teams as small as seven all the way up to brigades of 5,000 soldiers.

Active duty personnel (excluding Coast Guard): 2,740

Army: Chief Warrant Officer 4

Navy: Chief Warrant Officer 4

Air Force: —

Marine Corps: Chief Warrant Officer 4

Coast Guard: Chief Warrant Officer 4

W-4 warrant officers are the most knowledgeable and capable technical experts in their field and they're charged with complex and important tasks. In the Army, for example, a chief warrant officer 4 might be ordered to integrate forces across the organization, like armor, infantry, and aviation.

Active duty personnel (excluding Coast Guard): 775

Army: Chief Warrant Officer 5

Navy: Chief Warrant Officer 5

Air Force: —

Marine Corps: Chief Warrant Officer 5

Coast Guard: —

Chief warrant officer 5 is probably the rarest rank in the U.S. Army. Any soldier who makes E-5 is a proven leader, innovator, and undisputed master of his or her specialty.

Active duty personnel (excluding Coast Guard): 22,874

Army: 2nd Lieutenant

Navy: Ensign

Air Force: 2nd Lieutenant

Marine Corps: 2nd Lieutenant

Coast Guard: Ensign

The most junior commissioned officer in the Coast Guard and Navy is called an ensign. In the Navy, ensigns must serve for two years before being promoted and might spend that entire time training if they want to be pilots, SEALs, or submariners. In the Army, 2nd lieutenants can be commanders or staff officers.

Active duty personnel (excluding Coast Guard): 29,477

Army: 1st Lieutenant

Navy: Lieutenant Junior Grade

Air Force: 1st Lieutenant

Marine Corps: 1st Lieutenant

Coast Guard: Lieutenant Junior Grade

The O-2 grade is a more experienced, more capable junior officer than O-1. They generally have served at least one deployment and have commanded a group of personnel. In the Marines, aviators generally join their first squadron as 1st lieutenants.

Active duty personnel (excluding Coast Guard): 73,176

Army: Captain

Navy: Lieutenant

Air Force: Captain

Marine Corps: Captain

Coast Guard: Lieutenant

In the Army, captains command company-sized elements. About 1 in 3 active duty Marine Corps officers are captains, and captains in the Air Force arrive at that rank after serving four years as an officer. Whether they're called lieutenants or captains, the O-3 grade comes with enhanced responsibility and the expectation of mentoring junior officers.

Active duty personnel (excluding Coast Guard): 42,229

Army: Major

Navy: Lieutenant Commander

Air Force: Major

Marine Corps: Major

Coast Guard: Lieutenant Commander

Majors are field officers who serve in battalion- or brigade-sized elements. The Army often sponsors and pays for them to go to graduate school or professional development school in exchange for greater service. They generally serve as executive officers and operations officers.

Active duty personnel (excluding Coast Guard): 27,104

Army: Lieutenant Colonel

Navy: Commander

Air Force: Lieutenant Colonel

Marine Corps: Lieutenant Colonel

Coast Guard: Commander

Generally, lieutenant colonels are charged with commanding Army or Marine battalions. In the Coast Guard, commanders are the lowest senior officer. No matter the branch, O-5 comes with significant authority and responsibility.

Active duty personnel (excluding Coast Guard): 11,305

Army: Colonel

Navy: Captain

Air Force: Colonel

Marine Corps: Colonel

Coast Guard: Captain

Colonels in the Army command brigades or regiments in the Marines. They are the ultimate authority on everything that happens in their elements and they are ultimately responsible for everything their personnel do or do not do.  

Active duty personnel (excluding Coast Guard): 406

Army: Brigadier General

Navy: Rear Admiral (Lower Half)

Air Force: Brigadier General

Marine Corps: Brigadier General

Coast Guard: Rear Admiral (Lower Half)

In the Coast Guard, a rear admiral lower half is a seasoned, proven officer who commands a small flotilla of vessels. The same officer would also command a group of ships in the Navy. In both branches, O-7 represents the lowest rank of flag officers. In the other three branches, it's the lowest rank of general officer.   

Active duty personnel (excluding Coast Guard): 300

Army: Major General

Navy: Rear Admiral (Upper Half)

Air Force: Major General

Marine Corps: Major General

Coast Guard: Rear Admiral (Upper Half)

Like all generals, Army major generals are sometimes called by the number of stars in their insignia. At O-8, that is a two-star general. As division commanders, they are among the most respected and influential officers in the military and carry some of the heaviest responsibility.

Active duty personnel (excluding Coast Guard): 136

Army: Lieutenant General

Navy: Vice Admiral

Air Force: Lieutenant General

Marine Corps: Lieutenant General

Coast Guard: Vice Admiral

It is an honor for any officer to be appointed to the rank of lieutenant general. In most cases, the promotion is granted because the officer is appointed to a post that requires the rank by regulation, like Superintendent of the United States Military Academy at West Point.

Active duty personnel (excluding Coast Guard): 37

Army: General

Navy: Admiral

Air Force: General

Marine Corps: General

Coast Guard: Admiral

Although they are still general officers, generals are unique and distinct in that they are the only general officers to be addressed as "General." They hold the highest commands in the Army and may serve as members of the Joint Chiefs of Staff.