How many joules are in a British thermal unit?

1 BTU = 1055.06 J. To convert any amount, multiply by 1055.06.

How do you convert British thermal units to joules?

Multiply the number of British thermal units by 1055.06 to get joules. The formula is shown in the "How it's calculated" section above.

Where does the conversion factor come from?

It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.

Unit converter — Energy

British thermal units to joules converter

Convert British thermal units (BTU) to joules (J). Source-cited conversion factor, exact to the displayed precision.

Results are mathematically exact for the displayed precision. How we calculate.

How it's calculated

Convert British thermal units to joules— the formula

British thermal units convert to joules by multiplying by the published conversion factor. The factor below is exact to the precision shown, sourced from the citation under the formula.

J = BTU × 1055.06

BTU = J × 0.000948

Joule: SI derived. 1 cal (thermochemical) = 4.184 J exactly; 1 kcal = 1000 cal. 1 kWh = 3,600,000 J exactly. 1 BTU (IT) = 1055.05585262 J (NIST SP 811).

Questions

Frequently asked questions

How many joules are in a British thermal unit?
1 BTU = 1055.06 J. To convert any amount, multiply by 1055.06.
How do you convert British thermal units to joules?
Multiply the number of British thermal units by 1055.06 to get joules. The formula is shown in the "How it's calculated" section above.
Where does the conversion factor come from?
It's a published international standard. Most are defined exactly by international agreement (e.g. 1 inch = 25.4 mm exactly, 1 lb = 0.45359237 kg exactly). Source citations are listed under the formula above.