Chief Petty Officer

Common military ranks in English
Navies	Armies	Air forces
Commissioned and Non-commissioned officers
Admiral of the fleet	Marshal or Field marshal	Marshal of the air force
Admiral	General	Air chief marshal
Vice admiral	Lieutenant general	Air marshal
Rear admiral	Major general	Air vice-marshal
Commodore	Brigadier or Brigadier general	Air commodore
Captain	Colonel	Group captain
Commander	Lieutenant colonel	Wing commander
Lieutenant commander	Major or Commandant	Squadron leader
Lieutenant	Captain	Flight lieutenant
Sub-lieutenant	Lieutenant or First lieutenant	Flying officer
Ensign	Second lieutenant	Pilot officer
Midshipman	Officer cadet	Flight cadet
Enlisted grades
Warrant officer or Chief petty officer	Warrant officer or Sergeant major	Warrant officer
Petty officer	Sergeant	Sergeant
Leading seaman	Corporal	Corporal
Seaman	Private	Aircraftman

A chief petty officer is a senior non-commissioned officer in many navies and coast guards.

"Chief petty officer" refers to two ranks in the Royal Canadian Navy. A chief petty officer 2nd class (CPO2) (premier maître de deuxième classe or pm2 in French) is equivalent to a master warrant officer in the Army and Air Force, and chief petty officer 1st class (CPO1) (premier maître de première classe or pm1) is equivalent to a chief warrant officer in the Army and Air Force. In spoken references, chief petty officers may be addressed as "chief" but are never addressed as "sir".

"Chief Petty Officer" is the second highest non-commissioned rank in the Royal Australian Navy.

Fleet chief petty officer is a commissioned and gazetted rank in Pakistan Navy above chief petty officer and below master chief petty officer. It is equivalent to the Pakistan Air Force warrant officer and the Pakistan Army subedar.

In the Royal Navy, the rank of chief petty officer comes above that of petty officer and below that of warrant officer class 2, which is being phased out. It is the equivalent of colour sergeant in the Royal Marines, staff sergeant in the Army, and flight sergeant in the Royal Air Force.

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