Convert joules, calories, kilocalories, kWh, BTU and electronvolts for physics, nutrition, electricity and HVAC work.
Use this energy converter to convert joules, kilojoules, calories, kilocalories, kWh, BTU, electronvolts, and other common energy units instantly. It is useful for physics, chemistry, nutrition, HVAC, electricity use, and appliance energy comparisons.
Common conversions include J to cal, kWh to BTU, kcal to kJ, and similar unit checks where the same energy value needs to be shown in a different system.
Most Common Conversion Factors
| J | kJ | Wh | kcal | |
|---|---|---|---|---|
| 1 J | 1 | 0.001 | 2.778 x 10-4 | 2.388 x 10-4 |
| 1 kJ | 1000 | 1 | 0.277778 | 0.238846 |
| 1 Wh | 3600 | 3.6 | 1 | 0.860421 |
| 1 kcal | 4186.8 | 4.1868 | 1.163 | 1 |
Energy Converter FAQs
An energy converter converts one energy unit into another, such as J, kJ, cal, kcal, kWh, BTU, or eV. It is useful whenever the same energy amount is expressed in different systems.
Enter the value, choose J as the source unit, and choose cal as the target unit. This is a common conversion when comparing scientific energy values with heat-related units.
Choose kWh as the source unit and BTU as the target unit. This is common in electricity, heating, cooling, HVAC sizing, and appliance energy comparisons.
J is the SI unit of energy. cal and kcal are common in heat and food energy contexts, kWh is widely used for electricity consumption, and BTU is common in heating and cooling systems.
Yes. On food labels, a capital-C Calorie usually means 1 kcal, which is equal to 1000 cal.
Use it for physics problems, nutrition checks, electricity use, HVAC comparisons, battery energy estimates, or any situation where energy data must be translated between unit systems.
Yes. It is especially useful for conversions involving kWh, BTU, and J when comparing appliance consumption, heating output, cooling demand, or energy cost assumptions.
