Free & Instant
Energy Converter
Convert between Joules, Calories, Kilowatt-hours, BTU and more — instantly and accurately.
Energy Converter
Enter a value and select units to convert.
Converted Value
1 J = 0.2390 calAbout Energy Conversion
Energy conversion lets you switch between SI units (Joules), food energy units (Calories, Kilocalories), electrical energy (Kilowatt-hours), and imperial heat units (BTU) used in appliances and HVAC systems.
Common Energy Conversions
| From | To | Multiply By |
|---|---|---|
| Kilocalorie | Joule | 4184 |
| Kilowatt-hour | Joule | 3600000 |
| BTU | Joule | 1055.06 |
| Calorie | Joule | 4.184 |
Frequently Asked Questions
What's the difference between a calorie and a Kilocalorie?+
A food "Calorie" (capital C) is actually a kilocalorie — 1,000 small calories. This is why food labels show "Calories" meaning kcal.
How many Joules are in a Kilowatt-hour?+
One kilowatt-hour equals 3,600,000 Joules (3.6 megajoules), commonly used to measure home electricity usage.