Energy Converter
Convert between energy units
Convert between energy units like joules, calories, kilocalories, watt-hours, and BTU. Useful for nutrition labels, science class, and comparing energy usage.
1 Kilowatt-hours =
3.600000e+6
Joules
How to Use This Calculator
- Enter the energy value you're converting.
- Choose the unit you're converting from.
- Choose the unit you're converting to.
- Read the converted value.
Why Use This Calculator?
- Comparing a food label's calories with kilojoules.
- Converting an electricity bill figure.
- Working through a physics problem.
Real-World Examples
1 kilowatt-hour
One kWh equals 3.6 million joules, or about 3,412 BTU.
200 food calories
200 kilocalories (the "Calories" on food labels) equals about 836.8 kilojoules.
Frequently Asked Questions
Are food calories the same as calories?
On nutrition labels, a "Calorie" (capital C) is actually a kilocalorie — 1,000 small calories. The calculator handles both.
What's a watt-hour?
It's the energy used by a 1-watt device running for one hour. Electricity bills are measured in kilowatt-hours (1,000 watt-hours).
What's a BTU?
British Thermal Unit — an older energy unit still used for heating and cooling equipment. One BTU is about 1,055 joules.
Important Disclaimer
Uses standard energy conversion factors. Results may be rounded for display.
Privacy
Your entries stay in your browser; nothing is sent or stored.