China is closing the gap and the breakdown has been done on the forum. It's not that far off, even senior US navy personal say this.
That being said the USN is top for sure and has overwhelming advantages in certain key areas e.g. carrier strike. China is second, the thing is no navy comes close to China so hence why they should stand on their own.
Yes , China is second
but the thing is No Navy comes close to USA
Aircraft Carrier
USA : 11
China : 3 + India : 2 + Russia 1 + The UK : 2 + France : 1 + Italy : 1 = total of 10
Amphibious Assault Ships
USA : 9
China : 3
AEWC
USA : 70 E-2D
China : 6 KJ-600
Stealth Fighter Jet
USA : 65-70 F-35C ( The Navy ) and 190 F-35B + 52 F-35C ( USMC )
China : 20-30 J-35 ( The Navy )
ASW Aircraft
USA : 130 P-8A
China : 50 KQ-200
Electronic Attack
USA : 153 EA-18G Growler
China : 20-30 J-16D ( but PLAAF )
Carrier based Fighter Jets
USA : 420+ F/A-18E/F Super Hornet
China : 80-90 J-15
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Nuclear powered Submarine
USA : 70
China : 32
Destroyers
USA : 75 .... ( USA has also 7 Cruisers )
China : 62 .... ( Chiha has also 44 Frigates )
Total VLS
USA : 9100-9400
China : 4400-4600
Quad-pack Capability
The United States Navy is mastering the Quad-Pack
The Chinese Navy currently has no operational quad-packed missiles in active service
Air Defense Missiles
USA : SM-3 and SM-6 ( unique in the world )
China : No equal to SM-3 and SM-6
SLBM
USA : 280 ( simultaneously deployed at sea )
China : 72 ( simultaneously deployed at sea )
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Space-integrated networking
USA : Global
China : Regional Focus (Dense over East/South China Seas)
The US Navy possesses such a power that there's a huge difference even between it and the second-ranked player.