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⚡ Energy Converter
Convert joules, kilojoules, calories, kilocalories, kilowatt-hours and BTU between physics, food and bills.
About this Energy Converter
This energy converter links the units of physics (joules), food labels (calories and kilocalories), electricity bills (kilowatt-hours, the 'units' you pay for) and heating (BTU). One kilowatt-hour is exactly 3.6 million joules, and the 'Calories' printed on food packets are actually kilocalories.
How to use it
- Enter the energy amount.
- Pick the unit it is in and the unit you want.
- Click Convert to see the answer and the full table.
Example
A 2,000 kcal daily diet is 8,368 kJ of energy, and running a 1 kW heater for an hour uses 1 kWh = 3,412 BTU.
Frequently asked questions
Is a food Calorie the same as a calorie?
No — food 'Calories' (capital C) are kilocalories: 1 food Calorie = 1 kcal = 1,000 small calories = 4,184 joules.
What is a BTU used for?
Heating and air-conditioning power. AC tonnage is based on BTU per hour: 1 ton of cooling ≈ 12,000 BTU/h.
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