Joules to Kilojoules
Type a value in Joules and get the result in Kilojoules, calculated exactly.
100 Joules = 0.1 Kilojoules
Precision
Exact factorThis result is exact.
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Formula
kJ = J × 0.001
To convert Joules to Kilojoules, multiply the value by 0.001.
Worked examples
- 1 J × 0.001 = 0.001 kJ
- 100 J × 0.001 = 0.1 kJ
- 50 J × 0.001 = 0.05 kJ
This factor is exact by definition.
Conversion table
| Joules (J) | Kilojoules (kJ) |
|---|---|
| 1 | 0.001 |
| 2 | 0.002 |
| 3 | 0.003 |
| 4 | 0.004 |
| 5 | 0.005 |
| 6 | 0.006 |
| 7 | 0.007 |
| 8 | 0.008 |
| 9 | 0.009 |
| 10 | 0.01 |
| 15 | 0.015 |
| 20 | 0.02 |
| 25 | 0.025 |
| 30 | 0.03 |
| 40 | 0.04 |
| 50 | 0.05 |
| 60 | 0.06 |
| 70 | 0.07 |
| 75 | 0.075 |
| 80 | 0.08 |
| 90 | 0.09 |
| 100 | 0.1 |
Values marked ≈ are rounded; the rest are exact.
Reverse table: Kilojoules to Joules
| Kilojoules (kJ) | Joules (J) |
|---|---|
| 1 | 1,000 |
| 2 | 2,000 |
| 3 | 3,000 |
| 4 | 4,000 |
| 5 | 5,000 |
| 6 | 6,000 |
| 7 | 7,000 |
| 8 | 8,000 |
| 9 | 9,000 |
| 10 | 10,000 |
| 15 | 15,000 |
| 20 | 20,000 |
| 25 | 25,000 |
| 30 | 30,000 |
| 40 | 40,000 |
| 50 | 50,000 |
| 60 | 60,000 |
| 70 | 70,000 |
| 75 | 75,000 |
| 80 | 80,000 |
| 90 | 90,000 |
| 100 | 100,000 |
Unit definitions
- Joules J
- The SI unit of energy: one newton acting over one metre, or one watt for one second.
- Kilojoules kJ
- Exactly 1000 joules.
Questions people ask
Joules to Kilojoules: what is the conversion factor?
One J is 0.001 kJ.
How do I convert Joules to Kilojoules?
Use the formula above. For example, 100 J = 0.1 kJ.
Is the conversion exact?
Yes. Both units have exact definitions, so the factor is exact; a result is only rounded when its decimals never end.
Factors checked 19 October 2026.