Energy Unit Converter | Convert between Joules, Calories, Kilowatt-hours and more

Online energy unit converter that supports precise conversion between joules, calories, kilowatt-hours, BTU and more energy units, providing professional results and reference knowledge.

Joule(J)
Current Unit
Calorie(cal)
Formula:1 J = 0.239006 cal
Calculation Process:0 J × 0.239006 = undefined cal
Watt-hour(Wh)
Formula:1 J = 0.000278 Wh
Calculation Process:0 J × 0.000278 = undefined Wh
Erg(erg)
Formula:1 J = 10000000 erg
Calculation Process:0 J × 10000000 = undefined erg
Kilojoule(kJ)
Formula:1 J = 0.001 kJ
Calculation Process:0 J × 0.001 = undefined kJ
Megajoule(MJ)
Formula:1 J = 0.000001 MJ
Calculation Process:0 J × 0.000001 = undefined MJ
Gigajoule(GJ)
Formula:1 J = 1.e-9 GJ
Calculation Process:0 J × 1.e-9 = undefined GJ
Terajoule(TJ)
Formula:1 J = 1.e-12 TJ
Calculation Process:0 J × 1.e-12 = undefined TJ
Millijoule(mJ)
Formula:1 J = 1000 mJ
Calculation Process:0 J × 1000 = undefined mJ
Microjoule(μJ)
Formula:1 J = 1000000 μJ
Calculation Process:0 J × 1000000 = undefined μJ
Nanojoule(nJ)
Formula:1 J = 1.e+9 nJ
Calculation Process:0 J × 1.e+9 = undefined nJ
Kilocalorie(kcal)
Formula:1 J = 0.000239 kcal
Calculation Process:0 J × 0.000239 = undefined kcal
Food Calorie(Cal)
Formula:1 J = 0.000239 Cal
Calculation Process:0 J × 0.000239 = undefined Cal
British Thermal Unit(BTU)
Formula:1 J = 0.000948 BTU
Calculation Process:0 J × 0.000948 = undefined BTU
Million BTU(MBTU)
Formula:1 J = 9.478134e-7 MBTU
Calculation Process:0 J × 9.478134e-7 = undefined MBTU
Kilowatt-hour(kWh)
Formula:1 J = 2.777778e-7 kWh
Calculation Process:0 J × 2.777778e-7 = undefined kWh
Megawatt-hour(MWh)
Formula:1 J = 2.777778e-10 MWh
Calculation Process:0 J × 2.777778e-10 = undefined MWh
Gigawatt-hour(GWh)
Formula:1 J = 2.777778e-13 GWh
Calculation Process:0 J × 2.777778e-13 = undefined GWh
Electronvolt(eV)
Formula:1 J = 6.241509e+18 eV
Calculation Process:0 J × 6.241509e+18 = undefined eV
Kiloelectronvolt(keV)
Formula:1 J = 6.241509e+15 keV
Calculation Process:0 J × 6.241509e+15 = undefined keV
Megaelectronvolt(MeV)
Formula:1 J = 6.241509e+12 MeV
Calculation Process:0 J × 6.241509e+12 = undefined MeV
Ton of TNT(ton TNT)
Formula:1 J = 2.390057e-10 ton TNT
Calculation Process:0 J × 2.390057e-10 = undefined ton TNT
Kiloton of TNT(kt TNT)
Formula:1 J = 2.390057e-13 kt TNT
Calculation Process:0 J × 2.390057e-13 = undefined kt TNT
Megaton of TNT(Mt TNT)
Formula:1 J = 2.390057e-16 Mt TNT
Calculation Process:0 J × 2.390057e-16 = undefined Mt TNT
Barrel of Oil Equivalent(bbl)
Formula:1 J = 1.634558e-10 bbl
Calculation Process:0 J × 1.634558e-10 = undefined bbl
Ton of Coal Equivalent(tc)
Formula:1 J = 3.412084e-11 tc
Calculation Process:0 J × 3.412084e-11 = undefined tc
Ton of Oil Equivalent(toe)
Formula:1 J = 2.388459e-11 toe
Calculation Process:0 J × 2.388459e-11 = undefined toe
Therm(thm)
Formula:1 J = 9.478134e-9 thm
Calculation Process:0 J × 9.478134e-9 = undefined thm
Foot-pound(ft·lb)
Formula:1 J = 0.737562 ft·lb
Calculation Process:0 J × 0.737562 = undefined ft·lb
Newton-meter(N·m)
Formula:1 J = 1 N·m
Calculation Process:0 J × 1 = undefined N·m

Energy Unit Knowledge

Basic Energy Units

Energy is a physical quantity that represents the capacity to do work. The basic energy unit in the International System of Units (SI) is the joule (J), defined as the work done by a force of 1 newton moving an object 1 meter in the direction of the force.

Common Energy Unit Conversions

  • 1 kilojoule (kJ) = 1000 joules (J)
  • 1 calorie (cal) = 4.184 joules (J)
  • 1 kilocalorie (kcal) = 4184 joules (J)
  • 1 kilowatt-hour (kWh) = 3,600,000 joules (J) = 3.6 megajoules (MJ)
  • 1 British Thermal Unit (BTU) = 1055.06 joules (J)
  • 1 electronvolt (eV) = 1.602176634×10^-19 joules (J).

Heat Units

  • Calories (cal) and British Thermal Units (BTU) are primarily used to measure heat energy. The food calorie (Cal, also known as the large calorie) is actually a kilocalorie (kcal), commonly used in food nutrition labels. 1 kilocalorie (kcal) = 1 food calorie (Cal) = 4.184 kilojoules (kJ)
  • 1 BTU is the amount of heat needed to raise the temperature of 1 pound of water by 1°F.

Electrical Energy Units

Watt-hours (Wh) and kilowatt-hours (kWh) are common units for electrical energy. 1 watt-hour represents the energy consumed by a device with a power of 1 watt operating for 1 hour, equal to 3600 joules. The kilowatt-hour is the standard unit for electricity billing, with 1 kilowatt-hour (kWh) = 1000 watt-hours (Wh) = 3.6 megajoules (MJ).

Energy Resource Units

  • Ton of oil equivalent (toe), ton of coal equivalent (tce), and TNT equivalent are units for measuring large-scale energy resources and explosive energy. 1 ton of oil equivalent is approximately 41.868 gigajoules
  • 1 ton of TNT equivalent is approximately 4.184 gigajoules, commonly used to express nuclear weapon yields
  • Barrel of oil equivalent is used in the petroleum industry, with 1 barrel of oil being approximately 6.1 gigajoules.

Energy Units in Different Fields

  • In physics, joules (J) and ergs are commonly used
  • In nutrition, calories (cal) and kilocalories (kcal) are used
  • The power industry uses kilowatt-hours (kWh) and megawatt-hours (MWh)
  • Nuclear physics uses electronvolts (eV) and its multiples
  • The energy industry uses barrels of oil equivalent, tons of oil equivalent, etc.
  • The HVAC industry commonly uses British Thermal Units (BTU).