Free tool
kJ to Calories Converter
Food labels in New Zealand and Australia lead with kilojoules, sometimes without a calorie figure at all, and UK and EU labels print kJ and kcal side by side. Convert either way using the exact 4.184 kJ per kcal factor.
Type into either field. 1 kcal = 4.184 kJ exactly, so 1 kJ = 0.239 kcal (rounded).
Quick reference
| Kilojoules | Calories (approx.) |
|---|---|
| 500 kJ | 120 kcal |
| 1000 kJ | 239 kcal |
| 1500 kJ | 359 kcal |
| 2000 kJ | 478 kcal |
| 8700 kJ | 2079 kcal |
Why some labels lead with kilojoules
New Zealand and Australia share a joint food standards code, and its Nutrition Information Panel format leads with energy in kilojoules. Calories, which are more familiar to people used to US-style nutrition labels, are not always shown at all. UK and EU labels print both units side by side. That unit difference is enough to trip up anyone, or any calorie tracker, that expects calories first.
SnapKai's nutrition label scanner reads kilojoule values directly from the packet as part of logging a food and converts them to calories for you.
Converting one number by hand is useful. Logging a whole day of food is faster with an app that reads the label for you.
Log your food and track calories with SnapKaikJ to calories: frequently asked questions
One kilocalorie (the "Calorie" used on food labels) equals 4.184 kilojoules exactly. To convert kJ to kcal, divide by 4.184. To convert kcal to kJ, multiply by 4.184.
The kilojoule is the standard metric unit of energy, and many countries show it on food labels. New Zealand and Australia share a joint food standards code that requires energy to be shown in kilojoules on the Nutrition Information Panel, with calories as an optional addition, so many packets show kJ only. UK and EU labels print kJ and kcal side by side, while US-style labels show Calories only.
1000 kJ is about 239 kcal, roughly the energy in a couple of slices of bread or a small chocolate bar, though the exact food matters far more than this single conversion.
Yes. SnapKai's nutrition label scanner reads kilojoule values directly off the label and converts them to calories as part of logging the food, so you do not need to convert anything by hand while using the app.
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