Energy Converter
Convert energy units instantly: joule, kilojoule, megajoule, calorie (thermochemical), kilocalorie (food Calorie), watt-hour and more. Precise factors, all units shown at once.
| Unit | Value |
|---|---|
| joule (J) | |
| kilojoule (kJ) | |
| megajoule (MJ) | |
| calorie (thermochemical) (cal) | |
| kilocalorie (food Calorie) (kcal) | |
| watt-hour (Wh) | |
| kilowatt-hour (kWh) | |
| electronvolt (eV) | |
| British thermal unit (IT) (BTU) | |
| foot-pound (ft·lbf) | |
| erg (erg) | |
| therm (US) (therm) | |
| ton of TNT (t TNT) | |
| tonne of oil equivalent (toe) |
Tip: double-click a row to convert from that unit. Click a value to copy it. Expressions like 3*12 are accepted.
How to use the Energy Converter
- Type the value you want to convert (expressions are allowed).
- Choose the unit you are converting from.
- Read the result in every other unit in the table — it updates as you type.
About this tool
Enter a value and choose its unit; the energy is converted to all 14 supported units simultaneously. Conversions use exact definitions where they exist (e.g. 1 inch = 25.4 mm, 1 lb = 0.453 592 37 kg).
Common conversions
| 1 J = 0.001 kJ | 1 kJ = 1000 J |
| 1 J = 0.000001 MJ | 1 MJ = 1 000 000 J |
| 1 J = 0.2390057361 cal | 1 cal = 4.184 J |
| 1 J = 0.0002390057 kcal | 1 kcal = 4184 J |
| 1 J = 0.0002777778 Wh | 1 Wh = 3600 J |
| 1 J = 2.777777778 × 10⁻⁷ kWh | 1 kWh = 3 600 000 J |