Relation Between Calorie and Joule

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Introduction to Calorie and Joule

Joule is the S.I. unit of heat (which is a form of energy and also a derived unit of energy and is a measure of doing work or generating heat) generally represented by "J”. It is equal to the energy transferred to a body when 1 N force acts on it to displace it by 1 m in the direction of the force.

1 Calorie is the amount of heat required at a pressure of 1 standard atmosphere to raise the temperature of 1gram (g) of water through 1 degree Celsius. 

Joule and Calorie both are units of heat or energy variously defined. The relation between Joule and Calorie can easily be depicted with a simple formula i.e. 

1 calorie (cal) = 4.184 (approx 4.2) Joule, which is wholly elaborated in this article 

How to Convert Joule Into Calorie?  

For International use, caloric is defined as the amount of heat required to raise the temperature of 1 gram (g) of water from 14.5 degrees Celsius to 15.5 degrees Celsius. 

Joules (J) and calories (Cal) are the most widely used energy and heat units. For joule calorie conversion it becomes more daunting tasks for the conversion of 1 joule to Calorie because it involves the division of the coefficient with a hectic value of 0.2390057361. It is quite a bit easier to convert Calorie into Joule as it involves the multiplication of coefficient with 4.18.

Quick Conversion Chart of Joule Into Calories


Calorie(TH) {Cal(TH)}

  0.01 J

      0.0023900574 cal (th)

  0.1 J

      0.0239005736 cal (th)

  1 J

      0.2390057361 cal (th)

  2 J

      0.4780114723 cal (th)

  3 J

      0.7170172084 cal (th)

  5 J

      1.1950286807 cal (th)

  10 J

      2.3900573614 cal (th)

  20 J

      4.7801147228 cal (th)

  50 J

      11.9502868069 cal (th)

  100 J

      23.9005736138 cal (th)

What is the Relation Between Calorie and Joule? 

As we know, energy is the ability to do work. Heat is also a form of energy. Both heat and energy can be measured using multiple units, and calories and joules are also examples of such heat units. 

And as you know, the relation between Calorie and Joule is proportional to each other which mean that any change in the Calorie (cal) will also lead to a change in its equivalent value in joules (J). It also implies that Joule (J) is directly proportional to Calorie (cal) which means that:

  • When the value in terms of Calorie (cal) increases, then its value in Joule (J) increases at a rate of 4.2.

  • When the value in terms of Calorie (cal) decreases, then its value in joules (J) decreases at a rate of 4.2.

Calories to Joules Formula

As you know, Calorie (cal) and Joule (j) are the most important physical quantity in physics. Hence, the conversion between Calorie and Joule and vice versa is crucial in solving Physics numerical. So scroll down to get the list consisting of various commonly used quantities.

Quick Grasp on Calorie to Joule Table

Calorie (cal)

Joule (J)

1 cal

4.184 J

20 cal

83.68 J

30 cal

125.52 J

40 cal

167.36 J

50 cal

209.2 J

100 cal

418.4 J

500 cal

2092 J

1,000 cal or 1 kcal

4184 J

5,000 cal or 5 kcal

20920 J

10,000 cal or 10 kcal

41840 J

Do You Know?

We use calories in food instead of joules, and you will be about to know the answer by reading the below text.

1 joule is the work required to exert 1 Newton (N) force on a body for a distance of about 1 meter (m). Also, it equals the energy of 1 watt (W) of power for 1 second (sec).

A calorie is the amount of energy needed to raise 1 gram of water temperature by 1 degree Celsius.

So, it seems more logical to use calories based on its definition as a unit of energy; it seems to be more reliable to use it as a unit of energy in the case of food energy. A larger calorie is used as food energy.

FAQ (Frequently Asked Questions)

1. What do you mean by 1-joule energy?

The Joule (symbol J) is the international system of units (S.I. Unit) of energy and heat, a measure of the capacity to do work or generate heat.1-joule energy equal to the work done or energy expended by 1 Newton (N) force acting over a body displacing it by 1 meter (m). Therefore, 1 joule equals 1 Nm. 1 J represents a smaller unit of energy; that’s why 1000 J kilojoules (kJ) is used.

2. What is the difference between smaller and larger calories?

Small Calorie (cal) is the energy needed to increase 1 gram of water by 1degree Celsius at a pressure of 1 atmosphere.

Large Calorie (Cal) is the energy needed to increase 1 kg of water by 1 degree Celsius at a pressure of 1 atmosphere.

The large Calorie is also known as food calorie and is used as a unit of food energy.

3. State the difference between Joule and calories.

Joule (J) and Calorie (cal) both seem to be a unit of energy, but they differ as they represent 2 different quantities. Joule and Calorie main difference is that Joule is a derived quantity of energy, work, and heat and an S.I. unit, whereas Calorie is the unit of energy.  

4. Convert 16,736 joules (J) to calories (cal)?


Joule (J) / 4.814 = calories (cal).


16,736 joule (J) / 4.184 = 4,000 joules (J)


16,735 joule (J) is equal to 4,000 joules (J).