British Thermal Units to Joules Converter

To convert a measurement in british thermal units to joules, multiply the value by 1,055.0559. The conversion factor comes from the relationship between both units and the joule.

For example, to convert 5 BTU to joules: 5 × 1,055.0559 = 5,275.2793 J.

A British thermal unit (BTU) is the energy needed to raise the temperature of one pound of water by one degree Fahrenheit, about 1,055 joules. The BTU arose from imperial heating and steam engineering. It remains the dominant unit for heating, ventilation, and air-conditioning capacity in the United States, where furnaces and air conditioners are rated in BTU.

Common uses of british thermal units include: Air conditioner and furnace ratings; Heating and cooling load calculations; Natural gas and fuel energy content; HVAC system sizing in the US.

A joule is the SI derived unit of energy, equal to the work done when a force of one newton moves an object one meter (1 N·m). Named after the English physicist James Prescott Joule, who established the mechanical equivalent of heat in the 1840s. The joule became the SI standard for all forms of energy, work, and heat.

Common uses of joules include: Scientific and engineering energy calculations; Nutrition labeling in metric countries; Mechanical work and kinetic energy; Electrical energy in physics (watt-seconds).

HVAC sizing and appliance shopping drive this conversion. US air conditioners and furnaces are rated in BTU, but international engineering uses joules, so translating an 80,000 BTU furnace to joules lets you compare heating output with metric-rated equipment.

Here are some common values converted:

1 BTU = 1,055.0559 J 5 BTU = 5,275.2793 J 10 BTU = 10,550.5585 J 50 BTU = 52,752.7926 J 100 BTU = 105,505.5853 J