From gallons to British thermal units (Btu), kilowatthours to megajoules, short tons to metric tons, this calculator converts from one energy unit to another. Btu content is based on data from the Monthly Energy Review, Appendices, August 2023.

Calculators for energy used in the United States

• Coal
• Electricity
• Natural gas
• Crude oil
• Gasoline
• Diesel fuel and heating oil
• Food calories

Note: Btu is British thermal units.

Coal conversion calculator

short tons Btu megajoules metric tons

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1 short ton=18,704,000 Btu (based on U.S. electric power sector consumption in 2023)

Electricity conversion calculator

kilowatthours Btu megajoules million calories

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1 kilowatthour=3,412 Btu (standard conversion factor)

Natural gas conversion calculator

cubic feet Btu megajoules cubic meters

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1 cubic foot=1,036 Btu (based on U.S. average of natural gas for end-use sectors in 2023, preliminary)

Crude oil conversion calculator

barrels Btu megajoules liters

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1 barrel=42 U.S. gallons=5,689,000 Btu (based on U.S. production in 2023, preliminary)

Gasoline conversion calculator

gallons Btu megajoules liters

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1 gallon=120,214 Btu (based on U.S. finished motor gasoline [includes fuel ethanol content] consumption at 5.05 million Btu per barrel in 2023; preliminary)

Diesel fuel and heating oil conversion calculator

gallons Btu megajoules liters

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1 gallon=137,381 Btu (for distillate fuel with 15 ppm or less sulfur content at 5.77 million Btu per barrel in 2023; preliminary)

Measuring energy in food

Food calories are a measure of energy in food. One food calorie is equal to 1,000 calories, or 1 kilocalorie. For example, the energy in a 300-food calorie ice cream cone is about the same as the amount of electricity required to light a 100-watt incandescent light bulb for 3.5 hours.

Food energy conversion calculator

food calories Btu megajoules kilowatthours

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1 food calorie=1,000 calories, or 1 kilocalorie, or 3.9683 Btu

Scientific notation explained

Scientific notation is a shorthand way of writing a number that has a lot of digits. For example, the number 525,000,000 could be written as 5.25E+08. The +08 indicates the decimal should be moved eight places to the right. A negative number after the E means the decimal should be moved a certain number of places to the left. For example, 5.25E-03 is the same as 0.00525.