Energy Converter
Convert between joules, calories, kWh, and BTU.
Ctrl+Enter to convert from first field
Common Conversions
| From | To | Multiply by |
|---|---|---|
| 1 kcal | joules | 4,184 |
| 1 kWh | BTU | 3,412.14 |
| 1 BTU | joules | 1,055.06 |
| 1 therm | BTU | 100,000 |
| 1 cal | joules | 4.184 |
| 1 kWh | kilojoules | 3,600 |
Frequently Asked Questions
How many calories are in a kilocalorie? +
One kilocalorie (kcal) equals 1,000 calories. The "Calories" listed on food labels are actually kilocalories. So a 200-Calorie snack bar contains 200 kcal or 200,000 small calories.
How do I convert kilowatt-hours to BTU? +
Multiply kWh by 3,412.14 to get BTU. For example, 1 kWh equals about 3,412 BTU. This conversion is common when comparing electricity usage to gas heating output.
What is an electronvolt used for? +
An electronvolt (eV) measures energy at the atomic and subatomic scale. It equals 1.602 x 10^-19 joules. Particle physicists use it to describe particle energies and mass-energy equivalences.
How many joules are in one calorie? +
One thermochemical calorie equals exactly 4.184 joules. This is the amount of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius.