Convert kilojoules to joules
1 kJ = 1000 J — exactly. Both units are defined against the SI, so this factor is a fraction, not an approximation.
1000J
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1 kJ = 1000 J
Show this value in all 39 energy & work units
- Petajoules PJ 1e-12
- Terajoules TJ 1e-9
- Gigajoules GJ 0.000 001
- Megajoules MJ 0.001
- Kilojoules kJ 1
- Joules J 1000
- Millijoules mJ 1 000 000
- Microjoules µJ 1 000 000 000
- Nanojoules nJ 1 000 000 000 000
- Watt-hours Wh 0.277 777 777 778
- Kilowatt-hours kWh 0.000 277 777 777 778
- Megawatt-hours MWh 0.000 000 277 777 777 778
- Gigawatt-hours GWh 2.77777777778e-10
- Terawatt-hours TWh 2.77777777778e-13
- Calorie (thermochemical)s cal 239.005 736 138
- Kilocalories kcal 0.239 005 736 138
- Calorie (IT)s cal (IT) 238.845 896 627
- Kilocalorie (IT)s kcal (IT) 0.238 845 896 627
- British thermal units BTU 0.947 817 120 313
- BTU (thermochemical)s BTU (th) 0.948 451 652 677
- Million BTUs MMBTU 0.000 000 947 817 120 313
- Therm (US)s thm 0.000 009 480 434 279 73
- Therm (EC)s thm (EC) 0.000 009 478 169 879 13
- Electronvolts eV 6.24150907446e+21
- Kiloelectronvolts keV 6.24150907446e+18
- Megaelectronvolts MeV 6 241 509 074 460 000
- Gigaelectronvolts GeV 6 241 509 074 460
- Teraelectronvolts TeV 6 241 509 074.46
- Ergs erg 10 000 000 000
- Foot-pounds ft·lbf 737.562 149 277
- Inch-pounds in·lbf 8850.745 791 33
- Foot-poundals ft·pdl 23 730.360 404 2
- Horsepower-hours hp·h 0.000 372 506 135 999
- Tonne of TNTs t TNT 0.000 000 239 005 736 138
- Kiloton of TNTs kt TNT 2.39005736138e-10
- Megaton of TNTs Mt TNT 2.39005736138e-13
- Hartrees Eₕ 2.2937122784e+20
- Rydbergs Ry 4.58742455679e+20
- Quads quad 9.47817120313e-16
Every row is Kilojoule (kJ) converted through the joule, in exact rational arithmetic.
How to convert kilojoules to joules
Multiply the number of kilojoules by 1000 to get joules.
The exact factor is 1000 .
Kilojoule to Joule conversion table
| Kilojoules (kJ) | Joules (J) |
|---|---|
| 1 kJ | 1000 |
| 2 kJ | 2000 |
| 3 kJ | 3000 |
| 5 kJ | 5000 |
| 10 kJ | 10 000 |
| 20 kJ | 20 000 |
| 25 kJ | 25 000 |
| 50 kJ | 50 000 |
| 100 kJ | 100 000 |
| 250 kJ | 250 000 |
| 500 kJ | 500 000 |
| 1000 kJ | 1 000 000 |
Joule to Kilojoule conversion table
| Joules (J) | Kilojoules (kJ) |
|---|---|
| 1 J | 0.001 |
| 2 J | 0.002 |
| 3 J | 0.003 |
| 5 J | 0.005 |
| 10 J | 0.01 |
| 20 J | 0.02 |
| 25 J | 0.025 |
| 50 J | 0.05 |
| 100 J | 0.1 |
| 250 J | 0.25 |
| 500 J | 0.5 |
| 1000 J | 1 |
Frequently asked
How many joules are in a kilojoule?
One kilojoule equals 1000 joules (kJ → J). That figure is exact, not rounded.
How do you convert kilojoules to joules?
Multiply the number of kilojoules by 1000 to get joules.
What is 1 J in kilojoules?
One joule is 0.001 kilojoules.
What is 10 kJ in J?
10 kJ = 10 000 J.