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Joule (J)

The SI unit of energy: one newton-meter.

Result0.001

1 joule = 0.001 kilojoules

Joule at a glance

Unit nameJoule (plural: joules)
SymbolJ
Quantity measuredEnergy
Measurement systemSI
Also known asj, joules
Definition exact?Yes — exact by definition

1 joule in other energy units

Unit1 J equals
Kilojoule0.001 kJ
Megajoule0.000001 MJ
Calorie0.239005736 cal
Kilocalorie0.000239006 kcal
Watt-hour0.000277778 Wh
Kilowatt-hour0.000000278 kWh
Megawatt-hour2.77777778 × 10⁻¹⁰ MWh
Electronvolt6.24150907 × 10¹⁸ eV
British thermal unit0.000947817 BTU
Therm9.4781712 × 10⁻⁹ thm
Foot-pound0.737562149 ft·lb

Popular joule conversions

Frequently asked questions

What is a joule?
The SI unit of energy: one newton-meter.
What is the symbol for the joule?
The symbol for the joule is J. It measures energy.
How many kilojoules are in a joule?
1 joule = 0.001 kilojoules.
How many kilocalories are in a joule?
1 joule = 0.000239006 kilocalories.
How many kilowatt-hours are in a joule?
1 joule = 0.000000278 kilowatt-hours.