About this Energy Converter
Energy Converter translates common energy units used in electricity, physics, food-energy labels and technical calculations. The calculator keeps small calories and kilocalories as separate units.
Formula or method
The entered energy is converted to joules first, then converted from joules to the selected output unit.
Example
1 kilowatt-hour equals 3,600,000 joules, and 1 kilocalorie is approximately 4,184 joules.
Common uses
- Convert electrical energy between watt-hours and kilowatt-hours.
- Translate physics values between joules and kilojoules.
- Compare calories and kilocalories with joule-based units.
How to use this tool
- Enter the values or text requested by the calculator.
- Choose units or options when the tool provides them.
- Select the calculation button and review the result.
- Use the formula, example and notes on this page to check whether the result fits your situation.
Important note
Food “Calories” commonly refer to kilocalories (kcal), not small calories (cal). Choose the correct unit for your source value.
Frequently asked questions
Is a food Calorie the same as a calorie?
A capital-C food Calorie normally means one kilocalorie, which equals 1,000 small calories.
How many joules are in 1 kWh?
One kilowatt-hour equals 3,600,000 joules.