Volcanic Explosivity Index
With an estimated Volcanic Explosivity Index (VEI) of 6, the eruption was equivalent to —about 13,000 times the nuclear yield of the Little Boy bomb (13 to 16 kt) that devastated Hiroshima, Japan, during World War II, and four times the yield of Tsar Bomba, the most powerful nuclear device ever detonated at 50 Mt.