Physics

Mass-Energy Calculator (E=mc²)

Calculate mass-energy equivalence using Einstein's famous equation

Solve For*

Mass

Energy

Energy

8.9876e+13J

The energy converted to joules

Energy in Kilowatt-hours

2.4965e+7kWh

The energy converted to Kilowatt-hours

Energy in Tons of TNT

2.1481e+4kg TNT

The energy converted to Tons of TNT

E = mc²
m = E / c²

c = 299,792,458 m/s (speed of light)
1 kWh = 3.6 × 10⁶ J
1 kg TNT = 4.184 × 10⁹ J

Supported inputs

Input	Description
Solve For	The target variable you want to solve for (Energy or Mass) energy · mass
Mass (kg)	The mass to convert to energy
Energy (J)	The energy to convert to mass

Formula

E = mc²
m = E / c²

c = 299,792,458 m/s (speed of light)
1 kWh = 3.6 × 10⁶ J
1 kg TNT = 4.184 × 10⁹ J

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