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Convert Kilojoule to Calorie (th)

Please provide values below to convert kilojoule [kJ] to calorie (th) [cal (th)], or vice versa.

From: kilojoule
To: calorie (th)


Definition: The kilojoule is an SI (International System of Units) derived unit of energy that is equal to 1000 joules. The joule is defined as the amount of energy transferred to an object when a one newton force acts on an object in the direction movement through a distance of one meter.

History/origin: The kilojoule, like other SI derived units, uses SI prefixes to denote multiples or submultiples of the given unit. In this case, the prefix "kilo" is used to express a multiple of 1000.

Current use: In countries that have adopted SI, the kilojoule is widely used as a unit of food energy. In some cases, both kilojoules and kilocalories are displayed, though in countries such as the United States, only kilocalories are shown (often referred to as "Calories") on food labels. Aside from this everyday use, kilojoules are used within scientific contexts around the world.


Definition: A calorie (symbol: cal) is a unit of energy defined as the amount of energy required to increase the temperature of one gram of water by one °C. This is referred to as the small calorie or the gram calorie, and is equal to 4.1868 joules, the SI (International System of Units) unit of energy.

A large calorie (symbol: Cal), also known as a kilogram calorie (symbol: Cal), is technically a kilocalorie (symbol: kcal), the equivalent of 1000 small calories, but is also sometimes referred to as simply "Calorie." Large calories are usually used for labeling foods, and as such, is known as the food calorie.

History/origin: The term calorie comes from the Latin word "calor," which means heat. It was first defined as a unit of heat energy in 1824 by Nicolas Clement and appeared in French and English dictionaries between 1841 and 1867. The large calorie was introduced to the American public later, in 1887, by Wilbur Olin Atwater.

Current use: Although the calorie can be used with SI, since the official adoption of SI in 1960, the calorie is considered obsolete. Despite this, the large calorie is still widely used as a unit of food energy, alongside, or in place of the SI unit of food energy, the kilojoule. The use of a capital "C" in Calorie is intended to denote the use of kilocalories rather than calories denoting a single calorie. This is not often understood however, resulting in some confusion when foods are only labeled as Calories rather than kilocalories.

Calories are also used within scientific contexts, such as chemistry. In these contexts, the term being referenced is most often the small calorie, though measurements are often reported in kilocalories.

Kilojoule to Calorie (th) Conversion Table

Kilojoule [kJ]Calorie (th) [cal (th)]
0.01 kJ2.3900573614 cal (th)
0.1 kJ23.9005736138 cal (th)
1 kJ239.0057361377 cal (th)
2 kJ478.0114722753 cal (th)
3 kJ717.017208413 cal (th)
5 kJ1195.0286806883 cal (th)
10 kJ2390.0573613767 cal (th)
20 kJ4780.1147227533 cal (th)
50 kJ11950.286806883 cal (th)
100 kJ23900.573613767 cal (th)
1000 kJ239005.73613767 cal (th)

How to Convert Kilojoule to Calorie (th)

1 kJ = 239.0057361377 cal (th)
1 cal (th) = 0.004184 kJ

Example: convert 15 kJ to cal (th):
15 kJ = 15 × 239.0057361377 cal (th) = 3585.086042065 cal (th)

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