Mass-Energy Calculator Formula

Understand the math behind the mass-energy calculator. Each variable explained with a worked example.

Use the Mass-Energy Calculator

Formulas Used

Energy (J)

energy_j = mass * pow(299792458, 2)

Energy (MeV)

energy_mev = mass * pow(299792458, 2) / 1.602e-13

Energy (kWh)

energy_kwh = mass * pow(299792458, 2) / 3.6e6

Variables

VariableDescriptionDefault
massMass(kg)1

How It Works

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.

Worked Example

1 kg of matter fully converted to energy.

mass = 1
  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.

Ready to run the numbers?

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