Converting calories to kilojoules is essential for understanding energy content in foods and managing dietary intake. A calorie (cal) is a unit of energy defined as the amount of heat needed to raise the temperature of one gram of water by one degree Celsius. In nutritional contexts, the term "Calorie" (with an uppercase 'C') refers to a kilocalorie (kcal), which equals 1,000 small calories. The International System of Units (SI) uses the joule (J) as the standard unit of energy, and one kilocalorie is equivalent to 4.184 kilojoules (kJ). Therefore, to convert Calories to kilojoules, multiply the number of Calories by 4.184. For example, a food item containing 250 Calories provides 1,046 kilojoules of energy (250 × 4.184 = 1,046 kJ). Conversely, to convert kilojoules to Calories, divide the number of kilojoules by 4.184. Understanding this conversion is beneficial for interpreting nutritional information and managing energy intake.