Convert joules to kilojoules
1 J = 0.001 kJ — exactly. Both units are defined against the SI, so this factor is a fraction, not an approximation.
0.001kJ
As a fraction: 1/1000
1 J = 0.001 kJ
How to convert joules to kilojoules
Multiply the number of joules by 0.001 to get kilojoules.
The exact factor is 0.001 — as a fraction, 1/1000.
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 |
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 |
Frequently asked
How many kilojoules are in a joule?
One joule equals 0.001 kilojoules (J → kJ). That figure is exact, not rounded.
How do you convert joules to kilojoules?
Multiply the number of joules by 0.001 to get kilojoules.
What is 1 kJ in joules?
One kilojoule is 1000 joules.
What is 10 J in kJ?
10 J = 0.01 kJ.