Kilocalorie to Millijoule Converter

A kilocalorie (kcal), also called a food calorie or large calorie, is a unit of energy equal to 1,000 small calories or approximately 4,184 joules. It represents the energy needed to raise the temperature of one kilogram of water by one degree Celsius.

The kilocalorie was developed in the 19th century for measuring heat and energy, particularly in nutrition and metabolism studies. It became the standard unit for food energy content and metabolic energy measurements, though many countries have since adopted kilojoules for food labeling.

Kilocalories are widely used in nutrition and dietetics, particularly in the United States, for measuring food energy content and daily energy requirements. They're found on food labels, diet plans, exercise equipment, and in medical and fitness applications for energy balance calculations.

A millijoule (mJ) is a unit of energy equal to one thousandth of a joule (10⁻³ J). It represents small amounts of energy, typically found in electronic circuits, small mechanical systems, and precision energy measurements.

The millijoule became important with the development of precision electronics and small-scale energy measurements. It was particularly useful for measuring energy in electronic pulses, small mechanical impacts, and low-energy physical and chemical processes.

Millijoules are used in electronics for measuring pulse energy, in precision mechanics for small impact measurements, in laser technology for pulse energy, and in materials testing for small-scale energy absorption measurements.