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Free Energy Converter – Joules, Calories, kWh & BTU

Energy Converter changes joules, calories, kilowatt-hours, BTU, and more instantly online for free. Accurate energy unit conversion in your browser.

7 UnitsJoules · kcal · kWhFood & ElectricityCopy ResultsFree

Converted Values

Joule (J)
4184
Kilojoule (kJ)
4.184
Calorie (cal)
1000
Kilocalorie (kcal)
1
Watt-hour (Wh)
1.162222
Kilowatt-hour (kWh)
0.00116222
BTU
3.965667

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All conversions run locally in your browser. Nothing is uploaded.

How to Use Energy Converter

1

Enter a Value

Type your energy into the unit you already know, such as kcal or joules.

2

Read Every Unit

All other units update instantly so you can compare results at a glance.

3

Copy the Result

Copy the converted energy value you need for your task.

Convert Between Any Energy Units Instantly

The Helperzy Energy Converter changes any energy value from one unit to another the moment you type, covering joules, kilojoules, calories, kilocalories, watt-hours, kilowatt-hours, and BTU. Enter a figure once and every other unit fills in automatically, so you never have to remember that one kilocalorie is about 4,184 joules or that one kilowatt-hour is 3.6 million joules. Energy appears in many guises: food labels use kilocalories or kilojoules, electricity bills use kilowatt-hours, heating uses BTU, and physics uses joules. Converting between them by hand is tricky, so this converter applies the exact factors to keep your result accurate. People use it to compare food energy between kcal and kJ on nutrition labels, to understand electricity usage in kWh, to size heating and cooling in BTU, and for physics and chemistry problems. Because every unit updates together, you can read an energy value across systems at a glance. All calculations run locally in your browser with standard conversion factors, so the tool is fast, works without an internet connection once loaded, and never uploads anything. Your figures stay private on your own device.

Frequently Asked Questions – Energy Converter

Enter your value in the kilocalories field and the kilojoules result appears instantly. One kilocalorie equals about 4.184 kilojoules, and the Helperzy Energy Converter applies this factor automatically, which is handy for reading food labels.