Which countries use kJ on food labels?

December 21, 2025 •

4 min read

Across Australia and New Zealand, it is a legal requirement for most packaged food to display energy content primarily in kilojoules (kJ). This metric standard stands in contrast to the calorie-centric labeling prevalent in other parts of the world, creating confusion for global consumers.

Quick Summary

Many nations, including Australia, New Zealand, and members of the European Union, use kilojoules (kJ) for food energy on nutrition labels, while countries like the U.S. and Canada use kilocalories (kcal) or 'Calories'.

Key Points

Metric Standard: Countries like Australia, New Zealand, and China mandate the use of kilojoules (kJ) on food labels, aligning with the metric system.
Dual Labeling in Europe: The European Union requires both kilojoules (kJ) and kilocalories (kcal) to be displayed, accommodating both systems.
US Calorie System: The United States primarily uses kilocalories (often just called 'Calories') on its nutrition labels, a practice deeply rooted in historical precedent.
Easy Conversion: The conversion is straightforward: one kilocalorie (kcal) is equivalent to 4.184 kilojoules (kJ), allowing consumers to translate between units.
Menu Labeling: Beyond packaged goods, mandatory kJ menu labeling is also implemented in certain regions, such as various states in Australia, for fast-food items.
Consumer Education: Different labeling standards require consumer education to prevent confusion, with public health campaigns often launched in regions with mandatory kJ labeling.

The Kilojoule vs. Calorie Divide

The measurement of food energy is a crucial aspect of nutrition labeling, helping consumers make informed decisions about their diet. However, the units used—kilojoules (kJ) and kilocalories (kcal), commonly referred to as 'calories'—differ significantly depending on location. This divide stems from historical and regulatory practices, with metric-adopting countries favoring kilojoules as the International System of Units (SI) standard, while others have maintained the more traditional calorie system.

Countries Mandating Kilojoule (kJ) Labeling

Several nations have adopted the kilojoule as the primary or mandatory unit for energy content on food labels. This is often part of a broader commitment to the metric system.

Australia and New Zealand: Food Standards Australia New Zealand (FSANZ) mandates that energy be displayed in kilojoules. Kilocalories (kcal) can also be shown, but kJ must be the more prominent figure. This extends to menu labeling in fast food chains and other outlets.
European Union: Within the EU, food labels must display energy content in both kilojoules (kJ) and kilocalories (kcal). This dual approach helps cater to consumer preferences while adhering to SI units. The UK, following EU regulations, also uses both units on its labeling.
South Africa: Similar to Australia, South Africa predominantly uses kilojoules on its food labels. Local health organizations and dietitians also commonly refer to kJ for nutritional guidance.
China: Food labeling regulations in China require energy content to be listed in kilojoules (kJ).

Countries Using Kilocalorie (kcal) or 'Calorie' Labeling

In other parts of the world, particularly those with strong historical ties to the imperial system, the kilocalorie remains the standard for food energy.

United States: The U.S. exclusively uses 'Calories' (which actually refers to kilocalories) on its Nutrition Facts labels. This standard has been in place for decades and is deeply ingrained in consumer education.
Canada: While Canada has adopted metric measurements for many things, its food labeling still emphasizes 'Calories' (kcal). Kilojoules (kJ) may also be present, but calories are the primary unit for consumer messaging.

Navigating Global Food Labels: A Comparison

The following table provides a clear overview of how different regions approach energy labeling, which is helpful for international travelers or consumers purchasing imported goods.


Region	Primary Energy Unit	Secondary Energy Unit	Conversion Factor	Regulatory Body	Notes
Australia & New Zealand	Kilojoules (kJ)	Kilocalories (kcal), optional	1 kcal = 4.184 kJ	FSANZ	kJ must be displayed prominently.
European Union (EU)	Kilojoules (kJ) & Kilocalories (kcal)	Not applicable	1 kcal = 4.184 kJ	Food Safety Authorities	Both units are mandatory on labels.
United States (US)	Kilocalories (kcal), referred to as 'Calories'	Not applicable	1 kcal = 4.184 kJ	FDA	Only 'Calories' are legally required.
Canada	Kilocalories (kcal), referred to as 'Calories'	Kilojoules (kJ), often included	1 kcal = 4.184 kJ	Health Canada / CFIA	'Calories' are the primary unit.
South Africa	Kilojoules (kJ)	Kilocalories (kcal), optional	1 kcal = 4.184 kJ	Department of Health	kJ is the standard unit.
China	Kilojoules (kJ)	Not applicable	1 kcal = 4.184 kJ	Ministry of Health	kJ is the standard on labels.

Understanding the Different Energy Units

Kilojoules and kilocalories both measure the energy derived from food, but they are based on different scientific foundations. The kilojoule is the standard metric unit of energy, defined as the amount of energy transferred to a one-kilogram mass to accelerate it by one meter per second every second. A kilocalorie (kcal), on the other hand, is the amount of energy required to raise the temperature of one kilogram of water by one degree Celsius. The conversion factor is fixed: 1 kcal = 4.184 kJ. For consumers, this means a product with 100 kcal contains roughly 418 kJ of energy.

The Impact of Labeling Differences on Consumers

The variation in labeling can be confusing for consumers, especially those who travel frequently or are accustomed to a different system. For example, a person from the U.S. might be alarmed to see a product with 870 kJ listed on a menu in Australia, when the same item might show 208 kcal (an average adult's daily intake is around 8700 kJ or 2080 kcal).

Public health bodies often launch campaigns to educate citizens on their local labeling standards. In Australia, the government has implemented mandatory kilojoule labeling on fast-food menus to encourage healthier eating, accompanied by educational resources. Similarly, the EU's dual labeling serves to help consumers accustomed to either system.

Conclusion

The use of kilojoules on food labels is not a universal standard but is a requirement in many countries, particularly those that have adopted the metric system, such as Australia, New Zealand, and most of the European Union. In contrast, the United States, and to a lesser degree Canada, continue to prioritize kilocalories (or 'Calories'). While both units measure the same thing—food energy—the international differences necessitate consumer awareness and familiarity with the conversion factor to make accurate dietary comparisons.

For more detailed information on Australian food standards, you can visit the official website of the Food Standards Australia New Zealand (FSANZ).

Frequently Asked Questions

Kilojoules (kJ) and kilocalories (kcal, or 'Calories') are both units of energy derived from food, but they are based on different measurement systems. A kilojoule is the metric (SI) unit, while a kilocalorie is a more traditional, imperial unit.

To convert kilojoules (kJ) to kilocalories (kcal), you divide the kJ value by 4.184. For a rough, quick conversion, you can simply divide the kilojoule count by four.

The difference is largely due to historical and regulatory reasons. Countries that have adopted the metric system, particularly in the Southern Hemisphere and Europe, often use kilojoules, which is the SI unit for energy. The U.S. has a long-standing tradition of using the calorie system.

Canada's food labels, like those in the U.S., primarily use 'Calories' (kcal). However, kilojoule (kJ) values are also often included alongside the calorie count, especially for foods for special dietary use.

Yes, both are equally accurate measurements of energy. They are simply different units for measuring the same thing, much like using miles versus kilometers for distance.

In countries like Australia, mandatory menu labeling schemes mean that fast-food chains are required to display the kilojoule content of standard menu items, often on menu boards and digital screens.

No, if you are only shopping and consuming food locally, you will be fine focusing on the standard unit used in your region, whether that is kJ or kcal. The difference primarily matters when dealing with imported goods or traveling.