1 J = 0.001 kJ (joule → kilojoule)
1 J = 0.001 kJ
1 joule equals 0.001 kilojoules. To convert joules to kilojoules, multiply the joule value by 0.001. For quick reference: 1 J = 0.001 kJ, 5 J = 0.005 kJ, 10 J = 0.01 kJ, 100 J = 0.1 kJ.
Kilojoules = Joules × 0.001Joules to kilojoules divides by 1000. A 5000 J quantity is 5 kJ; a 250 000 J figure is 250 kJ. The kilojoule keeps energy values tidy at human and nutritional scale — food labels in most of the world lead with kJ (a banana is about 370 kJ). The conversion is a plain decimal shift; use joules for raw physics calculations and switch to kilojoules only for a readable final figure.
Start with your value in joules.
Multiply the joule value by 0.001. This is the exact conversion factor from joules to kilojoules.
The product is your value in kilojoules. For example, 5 J × 0.001 = 0.005 kJ.
The exact factor from joules to kilojoules is 0.001.
Kilojoules = Joules × 0.001
Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.
| Joules (J) | Kilojoules (kJ) |
|---|---|
| 0.001 J | 1.0000 × 10^−6 kJ |
| 0.01 J | 1.0000 × 10^−5 kJ |
| 0.1 J | 0.0001 kJ |
| 0.5 J | 0.0005 kJ |
| 1 J | 0.001 kJ |
| 1.5 J | 0.0015 kJ |
| 2 J | 0.002 kJ |
| 5 J | 0.005 kJ |
| 10 J | 0.01 kJ |
| 20 J | 0.02 kJ |
| 50 J | 0.05 kJ |
| 100 J | 0.1 kJ |
| 200 J | 0.2 kJ |
| 250 J | 0.25 kJ |
| 500 J | 0.5 kJ |
| 1000 J | 1 kJ |
| 2000 J | 2 kJ |
| 2500 J | 2.5 kJ |
| 3600 J | 3.6 kJ |
| 5000 J | 5 kJ |
| 7500 J | 7.5 kJ |
| 10000 J | 10 kJ |
| 25000 J | 25 kJ |
| 50000 J | 50 kJ |
| 100000 J | 100 kJ |
| 250000 J | 250 kJ |
| 500000 J | 500 kJ |
| 1000000 J | 1000 kJ |
| 2000000 J | 2000 kJ |
| 3600000 J | 3600 kJ |
| 5000000 J | 5000 kJ |
| 10000000 J | 10000 kJ |
| 25000000 J | 25000 kJ |
| 50000000 J | 50000 kJ |
| 100000000 J | 100000 kJ |
| 250000000 J | 250000 kJ |
| 500000000 J | 500000 kJ |
| 1000000000 J | 1000000 kJ |
| 2000000000 J | 2000000 kJ |
| 5000000000 J | 5000000 kJ |
| 10000000000 J | 10000000 kJ |
| 20000000000 J | 20000000 kJ |
| 50000000000 J | 50000000 kJ |
| 100000000000 J | 100000000 kJ |
| 1000000000000 J | 1000000000 kJ |
| 10000000000000 J | 10000000000 kJ |
| 100000000000000 J | 100000000000 kJ |
| 1000000000000000 J | 1000000000000 kJ |
| 10000000000000000 J | 10000000000000 kJ |
| 100000000000000000 J | 100000000000000 kJ |
A heartbeat releases about 1 J of mechanical work. Lifting an apple 1 m takes roughly 1 J.
The joule (J) is the SI derived unit of energy, work, and heat — defined as the energy transferred when a force of one newton acts over one meter. The joule is the standard unit in physics, chemistry, and most modern engineering documentation.
The kilojoule (kJ) equals exactly 1,000 joules. It is the standard unit on EU and many non-US nutrition labels — 1 dietary calorie ≈ 4.184 kJ. It also appears in industrial-process specifications and energy-storage ratings.