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Convert kj to joules

1 kilojoule equals 1,000 joules. Enter a value below to convert instantly.

1 kJ
1,000 J

Multiply the number of kilojoules by 1000 to get joules. How this is calculated

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Need the other direction? Convert joule to kilojoule →

Formula

Multiply the number of kilojoules by 1000 to get joules.

Step by step

  1. Start with 1 kJ.
  2. Multiply by the conversion factor 1000.
  3. 1 × 1000 = 1,000 J.

Kilojoules to Joules conversion table

Kilojoules (kJ) Joules (J)
1 1,000
2 2,000
5 5,000
10 10,000
20 20,000
50 50,000
100 100,000
500 500,000
1,000 1,000,000

Convert Kilojoule to other energy units

1 kJ expressed in every other energy unit on this site.

  • Joule J 1,000
  • Megajoule MJ 0.001
  • Gigajoule GJ 0.000001
  • Millijoule mJ 1,000,000
  • Microjoule µJ 1,000,000,000
  • Nanojoule nJ 1,000,000,000,000
  • Attojoule aJ 1e+21
  • Erg erg 10,000,000,000
  • Calorie (thermochemical) cal 239.00574
  • Kilocalorie kcal 0.23900574
  • Calorie (IT) cal(IT) 238.8459
  • Kilocalorie (IT) kcal(IT) 0.2388459
  • Megacalorie Mcal 0.00023900574
  • Watt-hour Wh 0.27777778
  • Kilowatt-hour kWh 0.00027777778
  • Megawatt-hour MWh 2.7777778e-7
  • Gigawatt-hour GWh 2.7777778e-10
  • Watt-second W·s 1,000
  • Kilowatt-second kW·s 1
  • Horsepower-hour hp·h 0.00037250614
  • British Thermal Unit BTU 0.94781712
  • BTU (thermochemical) BTU(th) 0.94845141
  • MBTU (thousand BTU) MBTU 0.00094781712
  • MMBTU (million BTU) MMBTU 9.4781712e-7
  • Therm (US) thm (US) 0.0000094804343
  • Therm (EC) thm (EC) 0.0000094781339
  • Ton-hour (refrigeration) ton·h 0.000078984761
  • Foot-pound ft·lbf 737.56215
  • Inch-pound in·lbf 8,850.7458
  • Foot-poundal ft·pdl 23,730.36
  • Kilogram-force Meter kgf·m 101.97162
  • Gram-force Centimeter gf·cm 10,197,162
  • Gram-force Meter gf·m 101,971.62
  • Kilogram-force Centimeter kgf·cm 10,197.162
  • Ounce-force Inch ozf·in 141,611.93
  • Horsepower-hour (metric) PS·h 0.00037767267
  • Electronvolt eV 6.2415091e+21
  • Kiloelectronvolt keV 6.2415091e+18
  • Megaelectronvolt MeV 6.2415091e+15
  • Gigaelectronvolt GeV 6,241,509,100,000
  • Hartree Eh 2.2937123e+20
  • Rydberg Ry 4.5874246e+20
  • Ton of TNT tTNT 2.3900574e-7
  • Kiloton of TNT ktTNT 2.3900574e-10
  • Megaton of TNT MtTNT 2.3900574e-13
  • Tonne of Oil Equivalent toe 2.388459e-8
  • Barrel of Oil Equivalent bboe 1.6345576e-7
  • Gigaton of TNT GtTNT 2.3900574e-16
  • Fuel Oil Equivalent (kiloliter) FOE (kL) 2.487709e-8
  • Fuel Oil Equivalent (US barrel) FOE (bbl) 1.5666399e-7

About the kilojoule

The kilojoule (kJ) is a SI unit of energy.

About the joule

The joule (J) is a SI unit of energy.

Where this conversion is used

Converting kilojoules to joules comes up when nutrition labels, electricity bills, heating, and physics.

Related conversions

Frequently asked questions

How many joules are in a kilojoule?

One kilojoule equals 1,000 joules.

How do you convert kilojoules to joules?

Multiply the number of kilojoules by 1000 to get joules.

What is 1 joule in kilojoules?

One joule equals 0.001 kilojoules.

When would I convert kilojoules to joules?

This conversion is common when nutrition labels, electricity bills, heating, and physics.

Conversion factors are based on internationally agreed unit definitions. See our methodology and sources for details on how these values are verified.