Energy Converter
A free, browser-based converter. Runs entirely in your browser — no sign up, nothing stored.
100% FreeRuns in your browserBasic
Convert energy
Amount to convert
From (the unit you have)
To (the unit you want)
Result
0.001
1 Joules (J) = 0.001 Kilojoules (kJ)
All units
- Joules (J)
- 1
- Kilojoules (kJ)
- 0.001
- Calories (cal)
- 0.239006
- Kilocalories (kcal)
- 0.000239
- Watt-hours (Wh)
- 0.000278
- Kilowatt-hours (kWh)
- 2.7778e-7
- British thermal units (BTU)
- 0.000948
How to use this calculator
- Enter the amount you want to convert.
- Choose the unit you have (From) and the unit you want (To).
- Read the result instantly — every other unit is listed too.
How it works
Converts between kilojoules, joules, kilocalories (1 kcal = 4.184 kJ) and watt-hours (1 Wh = 3.6 kJ).
Worked example
4.184 kJ. = 1 kilocalorie.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.