What is British thermal unit?

A British thermal unit (BTU) is an energy unit defined as the heat needed to raise one pound of water by one degree Fahrenheit. It is used in HVAC systems, heating and cooling equipment ratings, and natural gas billing in the United States.

What is calorie (thermochemical)?

The thermochemical calorie is a unit of energy equal to approximately 4.184 joules. It is used in chemistry and physics to express small heat quantities, particularly in thermochemical experiments.

Worked examples

1 British thermal unit = 252.16440072 calorie (thermochemical)

1 calorie (thermochemical) = 4.184 joule

More Energy conversions

• Convert British thermal unit to joule
• Convert British thermal unit to kilojoule
• Convert British thermal unit to kilowatt hour
• Convert British thermal unit to calorie (thermochemical)
• Convert British thermal unit to kilocalorie (dietary)
• Convert British thermal unit to watt hour
• Convert British thermal unit to megajoule
• Convert British thermal unit to electronvolt
• Convert British thermal unit to therm (US)

Assumption: calorie means thermochemical calorie, and therm means US therm.