Convert Joules to Kilojoules
One joule equals 0.001 kilojoules. Type any value to convert joules to kilojoules instantly — with a full reference table below.
Convert Joules to Kilojoules
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Conversion formula
To convert joules to kilojoules, multiply by 0.001. One joule equals 0.001 kJ, and one kilojoule equals 1,000 J.
Joules to Kilojoules table
About converting Joules to Kilojoules
Joules (J) and Kilojoules (kJ) are both units of energy. The exact factor is 1 J = 0.001 kJ, so multiply by 0.001 to go from joules to kilojoules (or divide to go back).
The conversion is exact and runs entirely in your browser. Need the reverse? Use the Kilojoules to Joules converter, or the full unit converter for every unit at once.
Frequently asked questions
How many kilojoules are in one joule?
One joule equals 0.001 kilojoules.
How do I convert joules to kilojoules?
Multiply the number of joules by 0.001. For example, 10 joules = 0.01 kilojoules.
What is 5 joules in kilojoules?
5 joules is 0.005 kilojoules.