The Soviets built 35,119 T-34 tanks, and 29,430 T-34-85 tanks.
The US (M4 Sherman) and USSR (T-34). The Soviet Union might state that they built the most. The United States might say that they built the most. Whichever...both the T34 & M4 were the most mass produced tanks during WWII.
49,000 were produced
Armor & Gun=Tank Only Armor=Armored Personnel Carrier Only Gun=Self Propelled Gun Nearly (close to & counting license built copies by other nations) 100,000 T54/T55 medium tanks have been built. Approximately 50,000 M4's & 50,000 T34's were built (and many still exist today in foreign armies). Discounting the thousands of M60's, T62's, T64's, T72's, T'80's, Centurions, Pattons, Leopards, Abrams, there are probably 1/2 million tanks existing in the world...operational and non-operational, in museums and in the field.
about 10000
Between 1933 and 1945, Germany built about 30,000 tanks and tank destroyers.
The father of one of histories most famous tanks, the T34, was the BT tanks. If it hadn't been for the BT tank and it's combat experience in 1939 at Nomonhan, the T34 would never have been born. And if it had been created at all, it would have been too late to participate in WWII. The BT stood for "fast tank" and in 1935 was probably the fastest and deadliest armed tank in the world with a high velocity 45mm tank gun. It's only weakness was it's gas engine, a fault that was corrected with it's son, the T34.
The first tanks were constructed of riveted steel. During the Vietnam War, the M48 Patton tanks were built of cast one piece steel. After the war, today's tanks are made of classified synthetics.
Panzer=Armor=tanks. Automobile makers generally produce tanks.
The T34 was an improved tank, designed by Mikhail Koshkin based upon the combat experience of the Soviet BT tanks during the Nomanhan battles in 1939 with Japan.
Ludwig Ewald von Kleist's company built the German tanks with the aid of paid workers and slave workers from the concentration camps. He was tried for war crimes after the war and imprisoned. He built the Panzer tanks.
Austria and Turkey did not use tanks. Germany built only twenty tanks, and they used captured British tanks which were in no short supply.
Technically speaking, there were actually many tanks that have participated in WW II. For example, there was a super heavy tank called the T28 equipped with the 120 mm gun, built to counter other super heavy tanks such as the German tank Maus. Another USA tank was the T29. The T29 also had "brothers and sisters". The T29 is a prototype heavy tank designed with the 105 mm. It was made along with 2 other prototypes called the T30 and the T34. The last tank made was the T32. The T32 was the real deal. There is also another USA tank called the M10 Wolverine. There are many many more USA tanks but I'm not sure when they were made.