Energy Converter
Convert energy between joules, calories, kilowatt-hours, BTU, and electronvolts.
Runs locally in your browser. Your input is not uploaded.
How to Use
- 1
Pick the source unit
Choose joules, calories, kcal, Wh, kWh, BTU, foot-pounds, or eV.
- 2
Enter values
Type one energy amount per line, e.g. 1000 or 2.5.
- 3
Read all conversions
Each value is displayed in all nine energy units — copy or download.
Frequently Asked Questions
- One calorie is exactly 4.184 joules, and one food Calorie (kcal) is 4,184 joules. Enter either and the tool converts across joules, kilojoules, watt-hours, BTU, and more.
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