Energy Converter (J, kJ, kWh, calories, BTU, ...)
Convert energy between joules, calories, watt-hours, kilowatt-hours, and BTU — useful for comparing nutrition labels, electricity bills, and heating/cooling specs. Runs entirely in your browser.
How it works
Every unit is converted through a common base unit — the joule. Note that food-label "calories" are actually kilocalories (1 kcal = 1000 cal) — this converter distinguishes the two, so double-check which one a source means before converting.
Common conversions
| From | To | Result |
|---|---|---|
| 1 kWh | MJ | 3.6 MJ |
| 1 kWh | BTU | 3412.14 BTU |
| 1 kcal | kJ | 4.184 kJ |
| 2000 kcal | kJ | 8368 kJ (a common daily energy reference) |
FAQ
Is a food "calorie" the same as a physics calorie?
No — a food-label Calorie (often capitalized) is a kilocalorie, 1000 small calories.
How many kWh is a BTU?
1 BTU ≈ 0.000293 kWh; equivalently, 1 kWh ≈ 3412 BTU.