Kilojoules to Joules
Convert kilojoules to joules (kJ to J). 1 kJ = 1,000 J. Use the calculator, formula and conversion table.
How to convert kilojoules to joules
Multiply the amount in kilojoules by 1,000 to get joules. The displayed factor and results are rounded to 12 significant digits.
J = kJ × 1,000Worked example
1 kJ = 1,000 J. Change the amount in the calculator above to use your own value.
Units and assumptions
A watt-hour is 3,600 joules. Calories use the thermochemical definition (4.184 J); BTU uses the International Table definition.
Calculator results use floating-point arithmetic and are rounded for display. The reference table below uses up to 12 significant digits.
Kilojoules to Joules table
| Kilojoules (kJ) | Joules (J) |
|---|---|
| 0 | 0 |
| 1 | 1,000 |
| 5 | 5,000 |
| 10 | 10,000 |
| 25 | 25,000 |
| 100 | 100,000 |
| 1,000 | 1,000,000 |
About this conversion
What is the formula for kilojoules to joules?
J = kJ × 1,000. Multiply the amount in kilojoules by 1,000 to get joules. The displayed factor and results are rounded to 12 significant digits.
How do I convert back to kilojoules?
Use the joules to kilojoules calculator to reverse this conversion. You can also use Swap units in the calculator above.
Can I use a different pair of units?
Choose another unit in the calculator, or open the energy converter to browse all supported pairs.