Free Mass-Energy Calculator

Calculate energy from mass using Einstein's famous equation E = mc².

kg

Energy (J)

89,875,517,873,681,760 J

Energy (MeV)561,020,710,821,983,600,000,000,000,000 MeV
Energy (kWh)24,965,421,632 kWh

Energy (J) vs Mass

Mass-Energy Equivalence

Einstein's equation reveals that mass and energy are interchangeable.

Formula

E = mc²

where c = 299,792,458 m/s is the speed of light. A tiny amount of mass corresponds to an enormous amount of energy. This is the principle behind nuclear power and nuclear weapons.

Example Calculation

1 kg of matter fully converted to energy.

  1. 01E = mc²
  2. 02E = 1 * (2.998e8)²
  3. 03E = 8.988e16 J
  4. 04E = 2.497e10 kWh
  5. 05That is about 21.5 kilotons of TNT equivalent.

Frequently Asked Questions

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