Mass-energy equivalence calculator
Because c is exact and enormous, a gram of anything is worth about 25 million kilowatt-hours — if you could release it all.
Energy
89 875 517 870 000J
- Same energy
- 24 965 422 kWh
- Same energy in kilotons of TNT
- 21.4808
- Years of electricity for an average home Taking 10 000 kWh a year.
- 2496.5
Show the working
- Mass = 1
- kg = 1 / 1000 = 0.001
- Energy = 0.001 * c^2 = 89 875 500 000 000
- Same energy = 89 875 500 000 000 / 3600000 = 24 965 400
- Same energy in kilotons of TNT = 89 875 500 000 000 / 4.184e12 = 21.4808
- Years of electricity for an average home = 24 965 400 / 10000 = 2496.54
Values are shown to six significant figures here; the arithmetic itself runs on exact fractions and is only rounded where a number is printed.
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The formula
- E = m c^2, with c exactly 299 792 458 m/s
The speed of light is exact by definition, so this conversion is an exact rational multiplication and is reported as exact.
Fission releases about 0.1% of the rest mass; chemical burning releases about a billionth of it.