<P> The United States Navy has 461 ships in both active service and the reserve fleet, with approximately 70 more in either the planning stages or under construction, according to the Naval Vessel Register and published reports . This list includes ships that are owned and leased by the U.S. Navy; ships that are formally commissioned, by way of ceremony, and non-commissioned . Ships denoted with the prefix "USS" are commissioned ships . Prior to commissioning, ships may be described as a "pre-commissioning unit" or PCU, but are officially referred to by name with no prefix . US Navy support ships are often non-commissioned ships organized and operated by Military Sealift Command . Among these support ships, those denoted "USNS" are owned by the US Navy . Those denoted by "MV" or "SS" are chartered . </P> <P> Current ships include commissioned warships that are in active service, as well as ships that are part of Military Sealift Command, the support component and the Ready Reserve Force, that while non-commissioned, are still part of the effective force of the U.S. Navy . Future ships listed are those that are in the planning stages, or are currently under construction, from having its keel laid to fitting out and final sea trials . </P>

How many ships does the united states navy have