How many different types of tanks were used during World War 2?

Answer 1

Naturally, it depends on what is mean by "types" of tanks.

If the question is referring to different models of tanks (similar to different models of cars, e.g. a Chevy Impala, Toyota Corolla, Toyota Camry, etc.), then, excluding specialty modifications (such as the amphibious modifications to certain M4 Shermans):

1. The British fielded about 24 different tank models, excluding those made by the USA. However, the vast bulk of the British tank force consisted of about 4 models.
2. The USA fielded about 7 different tank models, plus another 5 different tank destroyer models, which, from a design standpoint, should really be classified as tanks (unlike other countries' tank destroyers, which really were self-propelled artillery or assault guns). Once again, only about 4 models made up the bulk of production, with the M4 Sherman making up over 75% of all tanks produced.
3. The USSR fielded about 18 different tank models, with the T-34 making up the majority of their tank production.
4. The French had 10 different tank models, but saw virtually no action after the Fall of France in 1940.
5. The Italians fielded about 8 models, but none in large quantities.
6. The Japanese fielded about 15 tank models, plus another 4 different types of custom-design amphibious tanks. None were fielded in significant quantities.
7. Germany fielded 7 different models of tanks, plus over 20 models of tank destroyers, assault guns, and self-propelled artillery, though all of the latter lacked a turrent and should not really be classified as tanks in any way.

Most countries in WW2 began the war with a large variety of tank models designed in the 20s and 30s, virtually all of which were obsolete. In practically all cases, no more than 5 or 6 new models (from each country) were designed during the war, and the vast majority of tank production for the entire war centered around no more than 6 different models across all countries.

If the question is asking about the category of tank design (i.e. purpose/mission that the tank was designed to fulfill), then WW2 produced a myriad of different tank missions:

For the Allied powers, pre-war tank doctrine dictated three major categories of tanks:

1. Infantry-support: these were slower tanks, with heavy armor and powerful guns, intended to work in close-contact with infantry formations. In the British and French doctrine, these tanks (working in conjunction with special anti-armor artillery pieces) were intended to be the main anti-tank weapons. That is, enemy tanks were to be engaged by the Infantry-Support tank (as counterintuitive as that sounds)
2. "Cruiser" tanks, which included most Light and Medium tanks, where speed was th primary factor, with light armor and medium-caliber guns. These tanks were intended to be the "breakout" tanks, which would charge through openings that the infantry and infantry tanks would punch in enemy lines. As such, they were NOT primarily intended to be used against other tanks.
3. The tank destroyer, which was a particularly American ideology. These were medium tanks, build for very high speed and armed with a powerful gun, but with very little armor protection. Under American doctrine, the tank destroyer was the weapon to be used against enemy tanks, usually in a defensive roll.

In addition, the Allied forces produced a wide variety of add-ons and special mission conversions, numbering into the several dozen, including things such as amphibious kits, flamethrowers, mine-clearing, bridge-building, bulldozer, crane, and even rocket-launcher modifications.

As the war progressed, the Soviets were the first to discard this pre-war division, and focus on a more balanced design, combining mobility, good armor protection, and a powerful anti-tank gun. The outstanding medium T-34 and the solid heavy IS tanks were the result. The British eventually came around to this philosophy at the end of the war, producing the medium Cromwell and Comet which were good all-round designs. The Americans never did, however, instead pressing the M4 Sherman (a medium cruiser tank) into the utility roll, one which it was generally ill-suited for. Due to being knocked out early in the war, French tank designs never evolved.

German tank doctrine was different, generally delegating the infantry-support roll to the assault gun design, and assuming that tanks would be both mobile, and powerful enough to fight other tanks. While starting out with the generally weak Panzer I, II, and III models, the good Panzer IV was followed by the Tiger heavy tank, then the stellar Panther, followed by several increasingly ludicrous super-heavy designs (of which only the Tiger II saw any real action). Partially due to a change in war fortunes, German tank designs focused on producing increasingly powerful designs, intended to be able to beat any opponent in a 1-on-1 fight.

For both German and Allied designs, the light tank effectively disappeared after about 1942, as it was found extremely deficient in terms of protection (being vulnerable to even infantry-carried weapons) and not presenting enough firepower to be useful.

Frankly, neither the Italian nor Japanese tank forces developed effective tank doctrines, and neither really made much effort to develop new tank designs (or, for that matter, even manufacture many tanks).

Answer 2

Well over 100,000. The US had 88,000 Sherman tanks. But if you add all the other tanks from allies (esp. Russia's tanks) you are talking about over 100,000 tanks were used by the allies in the war.

Answer 3

The M3 medium tanks - commonly called the Sherman tank - were the mainstay of the American tank corp during World War II. Very late in the war, some General Chaffee and General Pershing tanks,larger and better armed - also got in to action.