Energy Converter
Calories, kilojoules, joules, kWh, Wh and BTU — food labels, electricity bills and physics in one place.
1 kcal = 4.184 kJ
All units
| joule (J) | 4184 |
|---|---|
| kilojoule (kJ) | 4.184 |
| calorie (cal) | 1000 |
| kilocalorie (kcal) | 1 |
| watt-hour (Wh) | 1.16222 |
| kilowatt-hour (kWh) | 0.00116222 |
| British thermal unit (BTU) | 3.96567 |
Common conversions
Formula: 1 kcal = 4.184 kJ
This tool runs entirely in your browser. Your data never leaves your device — it is not uploaded to any server.
How to use
- 1Type the amount you want to convert.
- 2Pick the unit you are converting from and the unit you are converting to.
- 3The result updates as you type — check the table below for every unit at once, or copy the result.
Energy Converter
Convert energy units across contexts: food calories (kcal) vs chemistry calories (cal), electricity in kWh, heating in BTU, physics in joules.
Clear distinction between cal and kcal — the mix-up behind many diet-label misunderstandings — with exact standard factors.
It supports 7 units — joule, kilojoule, calorie, kilocalorie, watt-hour, kilowatt-hour and more. Everything is calculated in your browser, works offline, and your data never touches a server.
Frequently asked questions
Is a calorie the same as a kilocalorie?
No. 1 kcal = 1000 cal. Food labels saying 'Calorie' (capital C) actually mean kilocalories. Enter 1 kcal → cal to verify.
How many kWh is 1 BTU?
1 BTU = 0.000293071 kWh. A 10,000 BTU air conditioner running for one hour uses about 2.93 kWh.
Is this converter free?
Yes — it runs entirely in your browser. There are no limits, no ads on results and no sign-up.
How accurate are the conversions?
Conversion factors follow international standard definitions (SI and NIST). Results are shown with up to 8 significant digits.
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