Convert Calorie (thermochemical) to British thermal unit

One cal equals 0.003965651243 BTU. This converter allows you to easily convert between Calorie (thermochemical) and British thermal unit in real time.

Formula

cal × 0.003965651243 = BTU

Example: 1 cal = 0.003965651243 BTU

What is Calorie (thermochemical)?

The thermochemical calorie is a unit of energy originally defined as the amount needed to raise the temperature of one gram of water by one degree Celsius. It is exactly 4.184 joules. Note that the "Calorie" seen on food labels is actually a kilocalorie (1,000 calories). The calorie has deep roots in calorimetry and chemistry, and although the SI system favors joules, calories remain widely used in everyday discussions of food and diet.

What is British thermal unit?

The British thermal unit is the amount of energy needed to raise the temperature of one pound of water by one degree Fahrenheit. It is primarily used in the American HVAC industry, where air conditioner capacity is rated in BTU per hour (12,000 BTU/h equals one ton of refrigeration). Residential air conditioners typically range from 5,000 to 25,000 BTU/h. Natural gas is also traded in BTU, with one cubic foot containing about 1,000 BTU. One BTU equals approximately 1,055 joules.