1. The conversion rate between kilojoules (kJ) and kilocalories (kcal), also known as calories, is 1 kJ equals approximately 0.2389 kcal.2. For instance, 837 kJ is equivalent to about 199.9593 kcal.3. Both kilojoules and kilocalories are units used to measure heat energy. The kilocalorie, commonly referred to as a calorie, is frequently used in nutrition and fitness.4. 1 calorie is equal to 1000 calories, and it is used to represent the heat energy content of food or fuel. For example, 1 kilogram of water absorbing or releasing heat to change its temperature by 1 degree Celsius is equivalent to 1 kilocalorie.5. The calorie (cal) is a common unit for assessing the energy value of fuels. A fuel's calorific value is expressed in "calories per kilogram" (X cal/kg), indicating the amount of heat released when a certain amount of fuel is burned.6. 1 calorie is equivalent to 4.2 joules. In heat energy unit conversions, 1 kilocalorie per kilogram (kcal/kg) is equal to 4.1868 kilojoules (kJ), which is also equivalent to 1 calorie per gram.7. The calorie is an energy unit defined as the amount of heat required to raise the temperature of 1 gram of water by 1 degree Celsius at standard atmospheric pressure. The calorie (cal) is widely used in nutritional and fitness contexts.8. Kilojoules (kJ) are the international units for measuring heat and work and should not be confused with kilograms (kg), which is a unit of mass. Kilojoules are commonly used to measure the caloric content of food and the energy expenditure of physical activity.