Joules to kilojoules converter
Kilojoules (kJ)
1 joule = 0.001 kilojoules
How to convert joules to kilojoules
kJ = J × 0.001
Multiply the number of joules by 0.001 to get kilojoules. Going the other way, divide by 0.001 (or multiply by 1000).
One joule is exactly defined as 0.001 kilojoules (to 12 significant figures), and one kilojoule is 1000 joules.
Worked examples
- Convert 5 joules: 5 × 0.001 = 0.005 0.005 kilojoules.
- Convert 12.5 joules: 12.5 × 0.001 = 0.0125 0.0125 kilojoules.
- Convert 250 joules: 250 × 0.001 = 0.25 0.25 kilojoules.
Quick-reference table
| J | kJ |
|---|---|
| 1 | 0.001 |
| 2 | 0.002 |
| 3 | 0.003 |
| 5 | 0.005 |
| 10 | 0.01 |
| 15 | 0.015 |
| 20 | 0.02 |
| 25 | 0.025 |
| 50 | 0.05 |
| 75 | 0.075 |
| 100 | 0.1 |
| 1,000 | 1 |
| kJ | J |
|---|---|
| 1 | 1,000 |
| 2 | 2,000 |
| 3 | 3,000 |
| 5 | 5,000 |
| 10 | 10,000 |
| 15 | 15,000 |
| 20 | 20,000 |
| 25 | 25,000 |
| 50 | 50,000 |
| 75 | 75,000 |
| 100 | 100,000 |
| 1,000 | 1,000,000 |
Related conversions
Frequently asked questions
How many kilojoules are in 1 joule?
1 joule equals 0.001 kilojoules.
What is the formula to convert joules to kilojoules?
Use kJ = J × 0.001. Multiply the number of joules by 0.001 to get kilojoules. Going the other way, divide by 0.001 (or multiply by 1000).
What is 100 joules in kilojoules?
100 joules is 0.1 kilojoules.