Calories to British Thermal Units

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cal
btu
1 cal = — btu

Quick reference

Calories (cal)British Thermal Units (btu)

Formula

British Thermal Units = calories × 0.0039656512

Multiply the calories value by 0.00396565124258336 to get british thermal units. To reverse — divide british thermal units by 0.00396565124258336 to get calories.

About this conversion

The calorie (cal) is the energy needed to raise 1 gram of water by 1°C, equal to approximately 4.184 joules. Learn more →

The British Thermal Unit (BTU) is the energy needed to raise one pound of water by 1°F, equal to approximately 1,055 joules. Widely used in HVAC and heating systems. Learn more →

Source: NIST International Reference