How to Convert kcal to kJ (and Back)
Kilojoules = kcal x 4.184. So 100 kcal = 100 x 4.184 = 418.4 kJ. To reverse: kcal = kJ / 4.184.
Open the interactive Everyday Lifestyle tool →Key facts
| kcal to kJ | kJ = kcal x 4.184 |
|---|---|
| kJ to kcal | kcal = kJ / 4.184 |
| 100 kcal | 418.4 kJ |
| 1 kcal | 4.184 kJ |
Frequently asked questions
What is 100 kcal in kJ?
418.4 kJ: 100 x 4.184 = 418.4 kJ.
What is 1000 kJ in kcal?
About 239 kcal: 1000 / 4.184 = 239 kcal.
Why do labels show both?
kJ is the SI energy unit; kcal is the traditional dietary unit. Both describe food energy.
Related pages
kcal to kJ Converter is part of Everyday Lifestyle on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.
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