Energy Converter

Energy is measured in joules in science, kilowatt-hours on electricity bills, calories on food labels, BTU and therms for gas and heating, and electronvolts in physics. This converter uses the standard definitions, including the thermochemical calorie (4.184 J) used on food labels, where one "Calorie" is a kilocalorie.

How to use Energy Converter

1. Type the value you want to convert.
2. Choose the unit you have in From and the unit you want in To. The swap button turns the conversion round.
3. Read the answer, with the formula underneath. For example, 1 kWh = 3.6 MJ ≈ 860 kcal.
4. Open All units to see the value in every unit at once, and copy the one you need.

When it comes in handy

• Comparing gas and electricity prices per kWh.
• Converting food energy between kcal and kJ.
• Physics and chemistry homework.

Frequently asked questions

Is a food Calorie the same as a calorie?

No. The Calorie on food labels (capital C) is a kilocalorie, 1,000 small calories or 4.184 kJ.

What is the difference between kW and kWh?

kW measures power (how fast energy is used); kWh measures energy (power × time). A 2 kW heater running for 3 hours uses 6 kWh. Use the Power Converter for kW.