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British thermal unit (BTU)

The heat needed to raise one pound of water by 1 °F; used for HVAC in the US.

Result1,055.055853

1 British thermal unit = 1,055.055853 joules

British thermal unit at a glance

Unit nameBritish thermal unit (plural: British thermal units)
SymbolBTU
Quantity measuredEnergy
Measurement systemUS customary
Also known asbtu, btus, british thermal units
Definition exact?No — factor is rounded

1 British thermal unit in other energy units

Unit1 BTU equals
Joule1,055.05585 J
Kilojoule1.05505585 kJ
Megajoule0.001055056 MJ
Calorie252.164401 cal
Kilocalorie0.252164401 kcal
Watt-hour0.29307107 Wh
Kilowatt-hour0.000293071 kWh
Megawatt-hour0.000000293 MWh
Electronvolt6.58514068 × 10²¹ eV
Therm0.00001 thm
Foot-pound778.169262 ft·lb

Popular British thermal unit conversions

Frequently asked questions

What is a British thermal unit?
The heat needed to raise one pound of water by 1 °F; used for HVAC in the US.
What is the symbol for the British thermal unit?
The symbol for the British thermal unit is BTU. It measures energy.
How many joules are in a British thermal unit?
1 British thermal unit = 1,055.05585 joules.
How many kilojoules are in a British thermal unit?
1 British thermal unit = 1.05505585 kilojoules.
How many kilocalories are in a British thermal unit?
1 British thermal unit = 0.252164401 kilocalories.