Convert kilojoule (kJ) to joule (J).
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Joule to Kilojoule Converter (J to kJ)
Convert joule (J) to kilojoule (kJ).Unit Converter · Energy
Quick answer
1 joule (J) is equal to 0.001 kilojoules (kJ). 1 kilojoule (kJ) is equal to 1,000 joules (J).
To convert J to kJ, multiply the value in joules by 0.001 (or divide by 1,000). For example, 10 J = 0.01 kJ, and 100 J = 0.1 kJ.
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Quick reference — joule to kilojoule
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How to convert joules to kilojoules
How many kilojoules are in a joule? 1 joule is 0.001 kilojoules. This free J to kJ converter and joule to kilojoule calculator gives the answer instantly for any value.
To convert joule (J) to kilojoule (kJ), multiply the value in joules by 0.001, or divide it by 1,000.
kJ = J × 0.001
- 1
Take the value in joules
For example, 25 J.
- 2
Multiply by 0.001
25 × 0.001.
- 3
Read the answer in kilojoules
25 J = 0.025 kJ.
Joule to Kilojoule conversion table
Common values from 1 to 1,000 joules converted to kilojoules.
| Joule (J) | Kilojoule (kJ) |
|---|---|
| 1 J | 0.001 kJ |
| 2 J | 0.002 kJ |
| 3 J | 0.003 kJ |
| 4 J | 0.004 kJ |
| 5 J | 0.005 kJ |
| 6 J | 0.006 kJ |
| 7 J | 0.007 kJ |
| 8 J | 0.008 kJ |
| 9 J | 0.009 kJ |
| 10 J | 0.01 kJ |
| 15 J | 0.015 kJ |
| 20 J | 0.02 kJ |
| 25 J | 0.025 kJ |
| Joule (J) | Kilojoule (kJ) |
|---|---|
| 30 J | 0.03 kJ |
| 40 J | 0.04 kJ |
| 50 J | 0.05 kJ |
| 60 J | 0.06 kJ |
| 70 J | 0.07 kJ |
| 75 J | 0.075 kJ |
| 80 J | 0.08 kJ |
| 90 J | 0.09 kJ |
| 100 J | 0.1 kJ |
| 250 J | 0.25 kJ |
| 500 J | 0.5 kJ |
| 1,000 J | 1 kJ |
About joules and kilojoules
Joule (J)
The joule (J) is the SI unit of energy: the work done by a force of one newton over one meter. One watt is one joule per second.
Kilojoule (kJ)
A kilojoule (kJ) is 1,000 joules. Food energy on nutrition labels is often shown in kJ as well as kcal.
J to kJ: common questions
- How many kilojoules are in 1 joule?
- 1 joule (J) is equal to 0.001 kilojoules (kJ). In short: 1 J = 0.001 kJ.
- How do I convert joules to kilojoules?
- To convert J to kJ, multiply the value in joules by 0.001 (or divide by 1,000). For example, 5 J = 0.005 kJ.
- How do I convert kilojoules to joules?
- To convert kJ to J, multiply the value in kilojoules by 1,000. Or open the Kilojoule to Joule converter, which does it for you.
- What is 10 J in kJ, and what is 100 J?
- 10 J = 0.01 kJ, and 100 J = 0.1 kJ. The table above lists more values from 1 to 1,000.
- Is this J to kJ converter accurate?
- Yes. It uses the exact conversion factor and shows results to as many as 8 decimal places, so you can rely on it for study, work and everyday measuring.
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