actually the "tzar" was the biggest nuclear bomb ever made
USSR they liked to think big cause they were really bad at acuracy.
Yield 100 Megatons
Weight approx. 27 tonnes (24.5 to 27.5 tonnes) [Janes Defense Weekly 1992]
Length 8 meters
Diameter (body) 2 meters
Little Boy weighed about 9,000 lbs. and had an explosive force (yield) equal to about 20,000 tons of TNT
I agree with matt (serial-thrilla) though.
I don't agreee with nuclear bombs at all
they shouldn't be used under any circumstances