Energy Converter
Convert between Joule, Kilojoule, Calorie, Kilocalorie, Watt-hour, Kilowatt-hour, BTU, Electronvolt, and Foot-pound instantly.
How do I convert Joules to Calories?
1 Calorie (cal) = 4.184 Joules. To convert Joules to Calories, divide the Joule value by 4.184.
How do I convert kWh to BTU?
1 kWh = 3412.14 BTU. Multiply the kWh value by 3412.14 to get BTU.
What is the difference between Calorie and Kilocalorie?
1 Kilocalorie (kcal) = 1000 Calories (cal). In food labeling, "Calorie" (capital C) typically means Kilocalorie.
What is an Electronvolt?
An Electronvolt (eV) is the energy gained by an electron moving across 1 volt. 1 eV = 1.602×10⁻¹⁹ J. It is used in particle physics.
What is a Watt-hour?
A Watt-hour (Wh) is a unit of energy equal to one watt of power expended for one hour. It is commonly used to measure electrical energy consumption.
How do I convert between different energy units?
Use the conversion factors: 1 J = 0.239 cal, 1 kWh = 3.6×10⁶ J, 1 BTU = 1055 J, 1 eV = 1.602×10⁻¹⁹ J. Enter the value and select the units to convert.
What is the SI unit of energy?
The SI unit of energy is the Joule (J). It is named after James Prescott Joule and is defined as the work done by a force of one newton acting through one meter.
Can I convert between mechanical and electrical energy?
Yes, energy can be converted between different forms. 1 kWh (electrical) = 3.6×10⁶ J (mechanical). The conversion is based on the principle of conservation of energy.
How to Use Energy Converter
Convert between Joule, Calorie, Kilowatt-hour, BTU, Electronvolt and other energy units instantly. All calculations run locally in your browser and nothing is uploaded.
- Type the energy value you want to convert into the input field at the top of the page.
- Select the source unit in the 'From' dropdown, for example Kilocalorie or Kilowatt-hour.
- Select the target unit in the 'To' dropdown, such as Joule, BTU or Watt-hour.
- Read the converted result, which updates immediately whenever you change the value or either unit.
- Open the 'Common References' section to compare everyday energy amounts such as food calories and household electricity.
Food labels count kilocalories, which equal 1000 small calories — pick Kilocalorie in the 'From' list rather than Calorie to avoid a 1000-fold error.
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