Calories vs Kilojoules
I know this may seem very basic to many of you out there, but I know that many still have this question, so let's unpack it. Calories vs Kilojoules, which should you focus on?
Calories vs Kilojoules: What’s the Difference and Why It Matters
When it comes to food labels and tracking energy intake, you've probably seen both calories (Cal) and kilojoules (kJ) used.
But what’s the actual difference between them — and do you need to pay attention to both?
Let’s break it down in simple terms.
Calories and Kilojoules Are Both Units of Energy
Just like kilometers and miles both measure distance, calories and kilojoules both measure energy.
The difference is in the system used:
Calories are part of the imperial system, mainly used in the United States and a few other countries.
Kilojoules belong to the metric system, and are commonly used in Australia, Europe, and many other parts of the world.
How to Convert Between Calories and Kilojoules
If you're switching between food labels or tracking apps from different regions, here’s a simple cheat sheet:
1 Calorie (Cal) = 4.184 kilojoules (kJ)
1 kilojoule (kJ) = 0.239 Calories (Cal)
Examples:
A 500 Calorie meal = about 2092 kJ
A 1000 kJ snack = about 239 Calories
Which One Should You Use?
It honestly depends on where you live and what your apps or food products use.
Most people only need to track one of them — either Calories or kilojoules — and understand how they relate to energy intake and fat loss.
If you're following a nutrition plan or using a calorie-tracking app, stick with whatever unit it uses.
Just know that they’re both measuring the same thing: how much energy your body gets from food.
Click here to get my eBook for recipes and for meal prepping - All nutritional values are listed in the eBooks.
Much Love
Mandy