Tsar Bomba Blast Radius size comparison
3,848 km2 / 1,485 mile2
The Soviet RDS-220 hydrogen bomb, also known as Tsar Bomba, was the most powerful nuclear weapon ever created and tested. Tested in 1961 as an experimental verification of calculation principles and multi-stage thermonuclear weapon designs, it also remains the most powerful human-made explosive ever detonated.
The explosion had a total destruction radius of 35 kilometers, and a fireball radius of 3.5 kilometers.