How to use the Energy Converter
- Type the energy amount you want to convert.
- Choose the unit you're converting from and the unit you want.
- Read the result instantly. Use the swap button to convert the other way.
- Check the tables below for every unit and common values.
What does this tool do?
Food labels use kilocalories (often written as Calories with a capital C) and kilojoules. One kilocalorie is 4.184 kJ. Electricity bills use kilowatt-hours, and heating and air conditioning often use BTU.
Why use it?
- Compare food labels from different countries.
- Convert heating and cooling ratings.
- Science and engineering conversions.
Common energy conversions
Quick reference:
| From | To |
|---|---|
| 1 kcal | 4.184 kJ |
| 2,000 kcal (daily intake) | 8,368 kJ |
| 1 kWh | 3,412 BTU / 3.6 MJ |
| 12,000 BTU (1 ton of cooling) | 3.517 kWh |
Privacy
The calculation happens instantly in your browser. The numbers you enter are not sent to our servers or saved. There's no account to create and nothing to install.
Frequently asked questions
How do I convert kcal to kJ?
Multiply by 4.184. A 2,000 kcal daily diet is about 8,368 kJ. Food labels in Australia, the UK and the EU often show both.
How many BTU are in a kilowatt-hour?
One kilowatt-hour is about 3,412 BTU. That's handy when comparing gas heating, which is often quoted in BTU or therms, with electric heating priced per kWh.
Last reviewed by the M2Toolkit team.