Joule (J)
The joule is a unit of energy, used for physics, electrical engineering, and scientific energy calculations. Its symbol is J.
J
kWh
1 joule equals
| Kilowatt-hours | 2.77778e-7 kWh |
| Kilocalories | 0.000239006 kcal |
| British Thermal Units | 0.000947817 BTU |
About the joule
The joule honors James Prescott Joule, the English physicist who demonstrated in the 1840s that heat and mechanical work are interchangeable forms of energy.
In everyday use the joule appears in physics, electrical engineering, and scientific energy calculations. As a point of reference: lifting an apple one meter takes about 1 joule of energy.