BTU to Kilocalorie Converter

A British Thermal Unit (BTU) is a unit of energy equal to approximately 1,055 joules. It represents the amount of energy needed to raise the temperature of one pound of water by one degree Fahrenheit at standard atmospheric pressure.

The BTU was developed in the 19th century as part of the British Imperial system for measuring heat energy. It became standard in heating, ventilation, and air conditioning (HVAC) applications in countries using imperial units, particularly for rating heating and cooling equipment capacity.

BTUs are extensively used in the United States for HVAC system ratings, heating and cooling equipment specifications, and energy content of fuels. They're standard for furnace output ratings, air conditioner capacity, water heater specifications, and natural gas energy content measurements.

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.