Energy converter

Joules to BTU Calculator

Convert energy in joules to British thermal units, kilojoules, and kilowatt-hours.

How Joules to BTU works

The British thermal unit is the energy needed to raise one pound of water by one degree Fahrenheit. In SI terms, one BTU (IT) equals 1,055.06 joules.

To convert joules to BTU, divide by 1,055.06. BTU is the standard energy unit for heating, air conditioning, and gas appliances in the US, so this conversion links scientific joule figures to HVAC ratings.

Formula

1BTU = J ÷ 1,055.06

1 BTU (IT) = 1,055.06 J. (The thermochemical BTU is 1,054.35 J.)

Joules to BTU conversion table

Reference Table5 rows

Common joule values converted to BTU (IT).
Joules↕	BTU↕	Kilojoules↕
1,055 J	1 BTU	1.055 kJ
10,000 J	9.48 BTU	10 kJ
100,000 J	94.8 BTU	100 kJ
1,000,000 J	948 BTU	1,000 kJ
3,600,000 J	3,412 BTU	3,600 kJ

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FAQ: Joules to BTU

How many joules are in a BTU?

One BTU (International Table) equals 1,055.06 joules. The thermochemical BTU is slightly smaller at 1,054.35 J.

How do you convert joules to BTU?

Divide the energy in joules by 1,055.06. For example, 1,000,000 J ÷ 1,055.06 ≈ 948 BTU.

How many BTU are in a kilowatt-hour?

One kilowatt-hour is 3,600,000 joules, which is about 3,412 BTU. This is why 1 kW of heating equals roughly 3,412 BTU/h.

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