Panzerkampfwagen VIII Maus: Weight, Size and the Story of the Biggest Tank Ever Built

The Panzerkampfwagen VIII Maus, often shortened to Panzer 8, is the largest tank ever completed, a 188-tonne German super-heavy design built during the final years of the Second World War. Only two prototypes were finished, and neither reached the battlefield in a usable state, but the Maus remains the standard reference point whenever the question "what is the biggest tank in the world" comes up.

Development began in 1942 under Ferdinand Porsche and Krupp, on Adolf Hitler's direct order for a super-heavy breakthrough tank far bigger than anything the German army had built before. What emerged by 1944 was, and still is, the biggest tank in WW2 and the heaviest fully armored fighting vehicle any nation has ever put into metal. The Maus is best known today by its ordnance series name, Panzerkampfwagen VIII, often shortened to Panzer 8 in modern references, or simply by its nickname, Maus (German for "mouse"), chosen after earlier code names "Mammut" (mammoth) and "Mäuschen" (little mouse) were considered.

Development History of the Panzerkampfwagen VIII Maus

Few super-heavy tank projects generated as much attention, then or now, as the Panzerkampfwagen VIII Maus. Ferdinand Porsche received the design contract in 1942, working under Hitler's direct order for a vehicle far heavier than any previous German tank. Krupp was responsible for the hull, armament and turret, while Alkett in Berlin handled final assembly. The original 1942 target called for a roughly 100-tonne vehicle armed with a 128 mm main gun and a coaxial 75 mm secondary gun; Hitler personally insisted on this exact combination in January 1943.

By May 1943, Krupp had built a full-scale wooden mockup of the design, and Hitler approved it for a production run of 150 vehicles after inspecting it. The estimated combat weight had by then grown to 188 tons. According to one frequently repeated account, Hitler later complained that the 128 mm gun looked like a "toy gun" against a hull this size and asked for it to be replaced with a 150 mm weapon, though the change was never carried out on either completed prototype.

Hitler cancelled the production order in October 1943, and in November 1943 development of the Maus was halted altogether, though work continued on the two prototypes already under construction. The first, turretless hull, known as V1, was completed by Alkett in December 1943 and began trials fitted with a dummy turret of the same weight as the real one. The second prototype, V2, followed in March 1944 and was eventually fitted with the first production turret, armed with the definitive 128 mm KwK 44 L/55 gun and coaxial 75 mm KwK 44 L/36.5 gun. By July 1944, Krupp was building four more hulls, but was ordered to scrap them; all work on the Maus stopped the following month, as Allied bombing and the deteriorating war situation made a super-heavy tank an unaffordable luxury.

Panzerkampfwagen VIII Maus Weight and Full Specifications

Maus tank weight reached 188 tonnes (207 short tons) in its final configuration, more than three times the combat weight of a Tiger I and close to double that of a Tiger II. The table below lists the specifications of the V2 prototype, the more completely equipped of the two vehicles built.

Maus Tank Armor Protection

The Maus carried the thickest armor of any tank built during the war, sloped where possible to increase its effective thickness against incoming fire. The hull front glacis plate was roughly 200 mm thick and steeply angled, the turret front was 220–240 mm, and the gun mantlet reached 250 mm at its heaviest point. Hull sides were 180 mm, the hull rear around 150–160 mm, and even the turret roof, at 60 mm, was thicker than the frontal armor of many contemporary medium tanks. Its 128 mm main gun, in turn, was powerful enough to destroy any Allied or Soviet armored vehicle at ranges beyond 3,500 meters — on paper, a combination of protection and firepower no other tank of the war approached.

Engine and Drive: How the Petrol-Electric Maus Moved

Rather than a conventional mechanical transmission, the Maus used a petrol-electric (and later diesel-electric) drive: the main engine turned a generator, which supplied electric motors mounted at each track, similar in principle to the drive system Porsche had already tried on the Elefant tank destroyer. The V1 prototype's Daimler-Benz MB 509 petrol engine produced around 1,080 hp, later replaced in V2 by a Daimler-Benz MB 517 diesel unit of roughly 1,200 hp, chosen partly because diesel fuel was in less demand from the Luftwaffe than aviation-grade petrol.

Even with this much power, the Maus was underpowered for its weight, and top speed never exceeded about 20 km/h under ideal conditions. Fuel capacity was 2,650–2,700 liters, plus a 1,500-liter reserve tank, giving a road range of roughly 160–190 km and barely 62 km cross-country. Those figures made sustained offensive operations far from a railhead impractical even before considering the tank's other limitations.

Panzerkampfwagen VIII Maus Size Compared to Other Super-Heavy Tanks

The table below offers a direct Maus tank size comparison against the German Tiger I and Tiger II, the Soviet IS-2 and the American M4 Sherman, the tanks most often used as a scale reference for it. This Maus tank size comparison shows that even the Tiger II, itself a nearly 70-tonne heavy tank, weighed barely more than a third as much as the Maus, and that four IS-2 heavy tanks could be built for roughly the weight of one Maus.

Why the Biggest Tank in the World Never Saw Combat

Heinz Guderian, the architect of German armored doctrine described on the Heinz Guderian: Panzer General page, was reportedly the only officer present at a 1944 demonstration who spoke against the Maus, objecting that it carried no machine gun for close-in defense and would be as vulnerable to infantry assault at short range as the Elefant tank destroyer had already proven to be.

The Maus failed for the same reasons that make any 188-tonne vehicle impractical: no bridge in Europe could support it, no engine of the era could move it at a useful speed, and no factory could build it fast enough to matter. Engineers tried to solve the bridge problem by designing the Maus to ford rivers instead of crossing them, submerging completely and drawing air through a snorkel long enough to let the crew breathe up to 13 meters (45 feet) underwater; a second Maus, connected by cable, was meant to supply electrical power to the submerged tank until it reached the far bank. In practice this meant Maus tanks could only operate in pairs, over rivers shallow enough to ford, a severe restriction for a vehicle already too heavy for most roads.

The bigger problem was power-to-weight ratio. The V1 prototype's petrol engine could only push the tank to about 13 km/h under ideal conditions, well short of the 20 km/h the design specification demanded, and the suspension needed constant rework to cope with the tank's weight. Production never resumed after Hitler's October 1943 cancellation freed Krupp and Alkett to focus on tanks that could actually reach the front, and by the time a fresh order might have been considered, Germany no longer had the industrial capacity, described in more detail on the German Tank Production in World War II page, to build a fleet of 188-tonne vehicles at all.

Fate of the Two Maus Prototypes

Both working prototypes remained at the Kummersdorf proving ground and at Böblingen through the last months of the war. In the war's final weeks, the V1 hull, still fitted with its dummy turret, was captured near Kummersdorf by advancing Soviet forces after German troops mechanically sabotaged it to prevent its use. The V2 prototype, carrying the real armed turret, was dispatched toward Berlin for the city's defense but broke down near Zossen and was blown up by its own crew to keep it out of enemy hands; it never fired a shot in anger.

The Soviet Commander of Armored and Mechanized Troops then ordered the V1 hull mated with the V2 turret, a job that required six 18-tonne half-tracks to lift the 55-tonne turret into place. The combined vehicle was finished in Germany under Soviet supervision and shipped to the USSR, arriving on 4 May 1946. Once testing was complete, it passed into storage at the Kubinka tank collection near Moscow, now part of Patriot Park, where the sole surviving Maus (engine, motors and interior fittings long since removed) remains on public display today.

The P.1000 Ratte and Other Super-Heavy Tank Projects

The Maus was the only German super-heavy tank design to reach the hardware stage; several more ambitious projects never got beyond paper or an unfinished hull. The Panzer VII Löwe ("Lion"), an 80–100 tonne design proposed before the Maus, was cancelled in July 1942 specifically so Krupp could concentrate on the heavier vehicle. The Krupp P.1000 Ratte, a 1,000-tonne landship intended to mount naval-caliber guns of the type used on the battleships Scharnhorst and Gneisenau, along with a 128 mm gun and eight 20 mm Flak 38 anti-aircraft guns, existed only as drawings before Albert Speer, the Reich's armaments minister, cancelled it in early 1943. The E-100, a 140-tonne design that shared some of the Maus's thinking but used a conventional mechanical transmission, got further than the Ratte: an incomplete hull was captured by American forces in April 1945 and later scrapped by the British in the 1950s.

Legacy of the World's Largest Tank

No nation has built anything close to the Maus in weight since 1945; postwar heavy tank designs stayed well under 70 tonnes, closer to the Tiger II than to Hitler's 188-tonne breakthrough tank. Every American tank built during the same war, cataloged on the American WW2 Tanks: The Complete US Army List of Tank Names page, weighed a fraction of the Maus yet reached the front in far greater numbers. The Maus survives mainly as an illustration of how far a single design requirement, armor and firepower with no upper limit, can be pushed before mobility and logistics stop being able to keep up. The lone surviving vehicle at Kubinka remains the only place anyone can see, in person, what the biggest tank in the world actually looked like.