Rank Structure

United States Navy
O-11 Fleet Admiral (FADM) [Special]
O-10 Admiral (ADM)
O-9 Vice Admiral (VADM)
O-8 Rear Admiral - Upper Half (RADM)
O-7 Rear Admiral - Lower Half (RDML)
O-6 Captain (CAPT)
O-5 Commander (CDR) 
O-4 Lieutenant Commander (LCDR)
O-3 Lieutenant (LT)
O-2 Lieutenant Junior Grade (LTJG)
O-1 Ensign (ENS)

W-5 Chief Warrant Officer (CWO5)
W-4 Chief Warrant Officer (CWO4)
W-3 Chief Warrant Officer (CWO3)
W-2 Chief Warrant Officer (CWO2)
W-1 Chief Warrant Officer (CWO1)

E-9 Master Chief Petty Officer of the Navy (MCPON) [Special]
E-9 Master Chief Petty Officer (MCPO)
E-8 Senior Chief Petty Officer (SCPO)
E-7 Chief Petty Officer (CPO)
E-6 Petty Officer First Class (PO1)
E-5 Petty Officer Second Class (PO2)
E-4 Petty Officer Third Class (PO3)
E-3 Seamen (SN)
E-2 Seamen Apprentice (SA)
E-1 Recruit 
****** MCPON is a singular rank, and FADM is a rank only for war times.