The World's Largest Submarines Ever Built
From the colossal Soviet Typhoon class to modern stealth attack boats, these are the biggest submarines ever to prowl the world's oceans. Ranked by length and displacement, each is an engineering marvel built for strategic dominance beneath the waves.
Size Comparison at a Glance
To put these machines in perspective: the Typhoon class at 175 meters is longer than a football field and a half. She displaces 48,000 tons submerged — more than many World War II battleships. The smallest submarine on this list, the British Astute class, is still nearly 100 meters long and displaces 7,400 tons. These are not small vessels by any measure.
Typhoon — 175 m
Typhoon — 48,000 t
Typhoon — 160
Top 10 Largest Submarines Ranked
Typhoon Class (Project 941 Akula)
The largest submarines ever built. These massive boats were designed to launch ballistic missiles from beneath Arctic ice. Their unique double-hull catamaran design created enormous internal volume — enough room for a swimming pool, sauna, and relatively spacious crew quarters. Six were built; only one (Dmitriy Donskoy) remains in service as a test platform.
175 m (574 ft)
48,000 tons
23 m (75 ft)
160
20 x R-39 SLBMs (200 nuclear warheads), 6 torpedo tubes
Columbia Class
The next-generation US Navy ballistic missile submarine, designed to replace the Ohio class. The Columbia class features a life-of-ship nuclear reactor that never needs refueling, electric-drive propulsion for reduced noise, and the X-stern configuration. Expected to serve into the 2080s. The first boat, USS District of Columbia (SSBN-826), is currently under construction.
171 m (560 ft)
20,815 tons
13 m (43 ft)
155
16 x Trident II D5LE SLBMs, planned life-of-ship reactor
Ohio Class
The backbone of the US nuclear deterrent for over four decades. Fourteen Ohio-class boats carry Trident II ballistic missiles, while four have been converted to guided-missile submarines (SSGNs) carrying up to 154 Tomahawk cruise missiles and Special Operations Forces. One of the most successful submarine classes ever built.
170 m (560 ft)
18,750 tons
13 m (42 ft)
155
24 x Trident II D5 SLBMs (or 154 Tomahawk cruise missiles on SSGN conversions)
Borei Class (Project 955)
Russia's newest ballistic missile submarines, designed to replace the aging Delta and Typhoon classes. The Borei class features a pump-jet propulsor for reduced acoustic signature, modern digital combat systems, and the new Bulava SLBM. The improved Borei-A (Project 955A) variant has been in production since 2020.
170 m (558 ft)
24,000 tons
13.5 m (44 ft)
107
16 x RSM-56 Bulava SLBMs, 6 torpedo tubes
Delta IV Class (Project 667BDRM)
The workhorse of Russia's nuclear deterrent during the late Cold War and beyond. The Delta IV class has been continuously upgraded with improved missiles and electronics. These submarines conduct regular deterrent patrols in the Arctic, where the ice cap provides natural concealment from detection.
167 m (548 ft)
18,200 tons
12 m (39 ft)
135
16 x R-29RMU Sineva SLBMs, 4 torpedo tubes
Oscar II Class (Project 949A Antey)
Massive cruise missile submarines designed specifically to sink US aircraft carrier battle groups. The Oscar II class carries 24 supersonic anti-ship missiles in paired launchers outside the pressure hull. The most infamous member of this class was the Kursk (K-141), which was lost with all 118 crew in the Barents Sea in August 2000.
155 m (508 ft)
24,000 tons
18.2 m (60 ft)
107
24 x P-700 Granit anti-ship missiles, 4 torpedo tubes, 4 torpedo tubes (650mm)
Vanguard Class
The four Vanguard-class submarines carry the United Kingdom's entire nuclear deterrent. Under Operation Continuous at Sea Deterrence (CASD), at least one Vanguard boat has been on patrol at all times since 1969. They will be replaced by the Dreadnought class from the early 2030s.
150 m (492 ft)
15,900 tons
12.8 m (42 ft)
135
16 x Trident II D5 SLBMs, 4 torpedo tubes
Triomphant Class
France's strategic nuclear deterrent submarines. The four Triomphant-class boats operate from Ile Longue near Brest, maintaining France's independent nuclear deterrent (Force de dissuasion). They feature pump-jet propulsion and advanced silencing technology, making them among the quietest SSBNs in the world.
138 m (453 ft)
14,335 tons
12.5 m (41 ft)
111
16 x M51 SLBMs, 4 torpedo tubes, SM39 Exocet anti-ship missiles
Virginia Class
The US Navy's current-production nuclear attack submarine, designed for the full spectrum of submarine operations in both deep water and littoral environments. Features photonic mast (no traditional periscope), fly-by-wire controls, and modular construction. Block V boats add the Virginia Payload Module with 28 additional Tomahawk missile tubes.
115 m (377 ft)
7,900 tons
10.4 m (34 ft)
135
12 x Tomahawk VLS, 4 torpedo tubes, mines, Virginia Payload Module (Block V+: 40 Tomahawks)
Astute Class
The Royal Navy's latest nuclear-powered attack submarines. The Astute class uses a PWR2 reactor with a 25-year life-of-ship core, meaning no refueling is ever needed. Their sonar suite (Sonar 2076) is considered one of the most capable in the world, able to detect ships leaving New York harbor from the English Channel according to the Royal Navy.
97 m (318 ft)
7,400 tons
11.3 m (37 ft)
98
6 torpedo tubes (Spearfish torpedoes, Tomahawk cruise missiles)
Why Do Submarines Keep Getting Bigger?
The trend toward ever-larger submarines is driven by several interrelated factors. Understanding them reveals why modern navies invest billions in these enormous vessels.
Strategic Missile Capacity
Ballistic missile submarines (SSBNs) are the most survivable leg of the nuclear triad. Their missiles require large, specialized launch tubes, and each submarine must carry enough warheads to represent a credible deterrent on its own. This drives enormous hull volumes. The Typhoon class was built around 20 massive R-39 missiles, each 16 meters long and 90 tons heavy — the missiles essentially dictated the submarine's size.
Stealth Through Size
Counterintuitively, larger submarines can be quieter. A bigger hull allows more space for vibration isolation mounts, acoustic decoupling, and machinery rafting — suspending noisy equipment on rubber mounts away from the hull. Larger submarines also have more room for advanced silencing technology like anechoic tile coatings and active noise cancellation systems.
Endurance and Habitability
Modern nuclear submarines deploy for 3-6 months at a stretch. Larger hulls provide more space for food storage, crew comfort, and life support systems. The US Navy has found that crew performance and retention improve significantly when submarine living conditions are less cramped. The Virginia-class Block V boats added a 25-meter hull plug specifically to increase payload capacity.
Multi-Mission Capability
Today's submarines are expected to do far more than torpedo enemy ships. They launch cruise missiles, deploy special operations forces, conduct intelligence gathering, lay mines, and serve as underwater command centers. Each additional mission requires space for equipment, weapons, and personnel. The four Ohio-class SSGNs each carry 154 Tomahawk missiles plus 66 special operators — a versatility only possible because of their enormous size.
The Arms Race Beneath the Waves
The competition to build bigger, quieter, and more capable submarines has not slowed since the Cold War. China is rapidly expanding its submarine fleet with the new Type 096 SSBN, expected to rival the Columbia class in capability. Russia continues building Borei-class boats. The UK's Dreadnought class and France's next-generation SNLE will both be larger than their predecessors.
Even nations without nuclear weapons are investing in larger conventional submarines. South Korea's KSS-III (Dosan Ahn Changho class) displaces 3,700 tons — enormous for a diesel-electric submarine — and carries ballistic missiles. Japan's Taigei class and Australia's planned SSN-AUKUS attack submarines represent billions in investment.
The submarine remains the most powerful and survivable naval weapon system in existence. As long as nations seek strategic advantage beneath the waves, submarines will continue to grow in size, capability, and cost.
Frequently Asked Questions
What is the largest submarine ever built?
The Soviet Typhoon class (Project 941 Akula) is the largest submarine ever built at 175 meters (574 feet) long with a submerged displacement of 48,000 tons. Only one remains in service as a test platform — the Dmitriy Donskoy. The Typhoon was so large it featured a swimming pool, sauna, and relatively spacious crew quarters.
How big is the largest US submarine?
The Ohio class is the largest US submarine at 170 meters (560 feet) and 18,750 tons submerged displacement. It will be succeeded by the Columbia class (171 meters, 20,815 tons) starting in the early 2030s. Ohio-class boats carry either 24 Trident II ballistic missiles or 154 Tomahawk cruise missiles.
Why are ballistic missile submarines so large?
Ballistic missile submarines (SSBNs) must carry intercontinental ballistic missiles that are typically 12-16 meters long and weigh 36-90 tons each. The missiles require large launch tubes, and the submarine must carry enough warheads to represent a credible nuclear deterrent. The weapons essentially dictate the submarine's minimum size.
Are bigger submarines quieter?
Counterintuitively, yes. Larger hulls provide more space for vibration isolation mounts, acoustic decoupling, and machinery rafting — suspending noisy equipment on rubber mounts away from the hull. Larger submarines also accommodate more advanced silencing technology like anechoic tile coatings and active noise cancellation.
How do the largest submarines compare to surface ships?
The Typhoon class at 48,000 tons submerged displacement exceeds many World War II battleships. Even the Ohio class at 18,750 tons is heavier than most modern destroyers. However, aircraft carriers (100,000+ tons) still dwarf even the largest submarines.
What is the largest submarine currently in production?
The Columbia class (SSBN-826) for the US Navy is the largest submarine currently under construction at 171 meters and 20,815 tons. Russia's Borei-A class (170 meters, 24,000 tons) is also in active production. Both are ballistic missile submarines designed for nuclear deterrent patrols.
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