You would think the answer to how many volcano’s there are would be a simple one. To be perfectly honest no one really knows the exact number. Part of the reason is what do you define as a volcano a vent, a field, one magma chamber and do inactive volcano’s count. The second reason that it’s so difficult to answer is that there are volcanic eruptions under the sea all the time and no one may be aware of them. Currently there are 20 active volcano’s around the world.