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BTU to Joules Converter

Convert BTU (BTU) to Joules (J) instantly, or use the conversion table below to look up common values.

1 BTU = 1,055.055853 J

BTU to Joules conversion table

BTU (BTU)Joules (J)
11,055.055853
22,110.111705
33,165.167558
44,220.22341
55,275.279263
1010,550.558526
2526,376.396316
5052,752.792631
100105,505.585262

How to convert BTU to Joules

1 BTU equals 1,055.055853 J. Use the converter above for any value, or read the table for common conversions.

J = BTU × 1055.05585262 · BTU = J × 0.0009478171203133172

Multiply a btu figure by 1,055.055853 to get joules, or divide it by 9.4782e-4 to go the other way.

Worked examples

  • 1 BTU= 1,055.055853 J
  • 5 BTU= 5,275.279263 J
  • 10 BTU= 10,550.558526 J
  • 100 BTU= 105,505.585262 J
  • 500 BTU= 527,527.92631 J

What these units are

BTU (BTU). A BTU (British thermal unit) is 1,055.05585262 joules — the energy needed to heat one pound of water by one degree Fahrenheit. It is used for heating and cooling capacity.

Joules (J). The joule is the SI unit of energy: the work done by one newton over one meter. It is used for small energy amounts in physics and engineering.

All factors are exact definitions, so only the display is rounded.

Converting BTU to Joules in practice

Reading the result in joules

Energy in the International System of Units is measured in joules, where one joule is the work done by a force of one newton moving an object one metre. The symbol is J.

Physics and engineering use the joule for mechanical work, heat, radiation and electrical energy, and small appliance labels sometimes state a surge or pulse rating in joules.

Multiples of the joule such as the kilojoule and megajoule are exact powers of one thousand, so no precision is lost. A watt is a rate rather than an amount, so it must be multiplied by time to yield joules.

The usual slip is to quote an electricity meter reading in joules when the meter counts kilowatt-hours. Both name energy, but the joule figure is 3.6 million times the kilowatt-hour figure.

The joule is the base unit, the kilojoule and megajoule are its decimal multiples, and the kilowatt-hour is the accounting unit an electricity meter counts. Joules suit physics and small quantities, while kilowatt-hours suit billing and storage capacity.

Checking a btu to joules conversion

Energy units are defined against the joule, so every conversion in this dimension is a single exact multiplication by a published number rather than a chain of steps that could accumulate error.

The pair that needs care is the kilowatt-hour, because it looks like a power unit and is not. It is a watt sustained for an hour, which is why an electricity meter counts in kilowatt-hours while a generator is rated in kilowatts: one is an amount, the other is a rate, and only a duration links them.

To check an energy conversion, express both sides in joules or both in kilowatt-hours before comparing. The commonest mistake is treating a food calorie as a calorie when the label means a kilocalorie, which understates the figure a thousandfold.

Tanzania reference points

Real quantities, converted into the units on this page.

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