…s exactly how much energy you’ll liberate whenever you make that conversion:…s exactly how much energy you’ll liberate whenever you make that conversion: from mass into energy. Specifically, for every 1 kilogram of mass you turn into energy, you get 9 × 10¹⁶ joules of energy out, which is the energy equivalent of 21 Megatons of TNT, or one of the most powerful hydrogen bombs ever detonated on Earth.