Kilojoules to Joules
Convert kilojoules (kJ) to joules (J) instantly — with formula and reference table.
kJ
J
Quick answer: 1 kJ = 1000 J. To convert kilojoules to joules, multiply by kJ × 1000.
Converting kilojoules to joules
This converter changes a value in kilojoules (kJ) into joules (J). One kilojoule equals 1000 J. One kilojoule equals exactly 1,000 joules. The conversion runs entirely in your browser — enter a value and the result updates instantly, in either direction.
Formula
J = kJ × 1000
Example
Convert 10 kJ to J: 10 × 1000 = 10000 J.
Kilojoules to Joules conversion table
| Kilojoules (kJ) | Joules (J) |
|---|---|
| 1 kJ | 1000 J |
| 2 kJ | 2000 J |
| 3 kJ | 3000 J |
| 5 kJ | 5000 J |
| 10 kJ | 10000 J |
| 20 kJ | 20000 J |
| 25 kJ | 25000 J |
| 50 kJ | 50000 J |
| 100 kJ | 100000 J |
How to use this converter
- Enter a value in the kilojoules (kJ) field.
- Read the converted value in joules (J) below.
- Type into the J field instead to convert in reverse, or use the swap button.
Frequently asked questions
How many joules are in a kilojoule?
1 kilojoule equals 1,000 joules.
How do I convert 5 kJ to joules?
5 times 1,000 = 5,000 joules.
How many joules in a food Calorie?
1 kcal equals 4,184 joules (4.184 kJ).