OzCal
Converter

kJ to calories converter

1 Cal = 4.184 kJ. To convert kilojoules to calories, divide by 4.184. To go the other way, multiply calories by 4.184. So 8,700 kJ is about 2,079 Cal, and 2,000 Cal is 8,368 kJ.

8,700 kJ = 2,079 Cal

Type in either box. 1 Cal = 4.184 kJ, the conversion Food Standards Australia New Zealand uses.

Conversion table

KilojoulesCaloriesRoughly
100 kJ24 CalA small piece of fruit
500 kJ120 CalA flat white with full cream milk
1,000 kJ239 CalTwo slices of buttered toast
1,500 kJ359 CalA standard sausage roll
1,700 kJ406 CalA 175 g meat pie
2,000 kJ478 CalA medium McDonald's fries and a nugget or two
2,700 kJ645 CalA Hungry Jack's Whopper
4,200 kJ1,004 CalAbout 1,000 calories
6,900 kJ1,649 CalA medium halal snack pack
8,700 kJ2,079 CalThe Australian daily average used on menu boards
10,000 kJ2,390 CalA loaded large HSP

Why Australian labels lead with kilojoules

Australia measures food energy in kilojoules because it uses the metric system. Packaged food panels, chain menu boards and the Australian Dietary Guidelines all lead with kJ. Calories survive in conversation because most fitness content is American.

The practical answer is to stop converting. If you track in the same unit your labels use, the number on the packet is the number you log, and the mental maths disappears.

Stop guessing the number

OzCal logs this in about five seconds: snap it, scan the barcode or say it. Kilojoules the way the label shows them, on 26,600 verified Australian foods.

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Common questions

How many kilojoules are in one calorie?

One calorie (Cal, the dietary kilocalorie) is 4.184 kilojoules. So 100 Cal is 418 kJ.

How do I convert kJ to calories in my head?

Divide by 4, then take off about 4%. 2,000 kJ is roughly 500 minus 20, so about 478 Cal.

How many calories is 8,700 kJ?

About 2,079 Cal. 8,700 kJ is the average adult daily energy intake used on Australian menu boards.

Why does Australia use kilojoules?

Australia uses the metric system for energy, so food labels, menu boards and dietary guidelines are written in kilojoules. Calories are still widely understood, which is why most Australian apps show both.

Is a calorie the same as a kilocalorie?

In food labelling, yes. The 'Cal' on a menu is 1,000 small calories, which is why the conversion is 4.184 kJ rather than 0.004184 kJ.

Keep reading

Citing this page. OzCal (2026). "kJ to Calories Converter (Australian Kilojoules) | OzCal". Retrieved from https://ozcal.com.au/kj-to-calories. Last updated 2026-09-15. Figures are per the serve stated in each row, converted at 1 Cal = 4.184 kJ. A plain-text version of this page is available at https://ozcal.com.au/kj-to-calories.md.

Where these numbers come from: Conversion factor: 1 dietary calorie = 4.184 kilojoules, the factor used in Australian food labelling. Example foods come from OzCal's catalogue. Figures are per 100 g or per the serve stated in each row, and real serves vary between stores, cooks and batches. Always check the label or the chain's own nutrition panel for the version in front of you. Energy converted at 1 Cal = 4.184 kJ. Last updated 2026-09-15.