Energy Converter
Enter an amount of energy, choose the unit it is in and the unit you want. You get the converted energy and a table of the same energy in every unit.
Your numbers
How we calculate it
Every amount is turned into joules and then into the unit you want. A thermochemical calorie is exactly 4.184 J, so a food Calorie (a kilocalorie) is 4,184 J. A watt hour is 3,600 J and a kilowatt hour is 3,600,000 J. A British thermal unit (International Table) is 1,055.05585262 J, and a foot pound force is 0.3048 × 0.45359237 × 9.80665 = 1.3558179483 J.
So 1 kilowatt hour is 3,412.14163313 BTU and 860.4207 food Calories. Results are shown to 12 significant digits.
Assumptions and limits
- The calorie that is written with a capital C on food labels is really a kilocalorie, 1,000 of the small calories.
- There are a few slightly different BTU and calorie definitions. This page uses the International Table BTU and the thermochemical calorie.
- Energy is not the same as power. A kilowatt is a rate, and a kilowatt hour is an amount.
Frequently asked questions
How many joules are in a kilowatt hour?
There are exactly 3,600,000 joules in a kilowatt hour, because a watt is a joule per second and an hour has 3,600 seconds.
How many calories are in a kilojoule?
One kilojoule is about 0.239 food Calories (kcal), and one food Calorie is 4.184 kilojoules.
How do I convert kWh to BTU?
Multiply the kilowatt hours by 3,412.14163. A heater that uses 1 kWh gives off about 3,412 BTU of heat.
Related calculators
- Pressure ConverterEnter a pressure, choose the unit it is in and the unit you want.
- Electricity Cost CalculatorEnter the power of an appliance in watts, the hours you use it each day you use it, how many days a week, and your electricity price per kWh.
- Calorie CalculatorEnter your sex, age, weight, height and how active you are.
- Weight ConverterEnter a weight, choose the unit it is in and the unit you want.
Worked example (a fixed example using the starting numbers, it does not change as you type)
Inputs: Value to convert = 1; From = kilowatt hour (kWh); To = British thermal unit (IT) (BTU).
- Result 3,412.14163313 BTU
- Conversion 1 kWh = 3,412.14163313 BTU
Embed this calculator
Add this calculator to your own page. Paste the code where you want it. The small link keeps credit to the source.