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Kilojoule [kJ] to Joule [J] Converter

Quick Reference

1 Kilojoule (kJ) = 1000 Joule (J)

1 Joule (J) = 0.001 Kilojoule (kJ)

How to Convert Kilojoule to Joule

1 kJ = 1000 J
1 J = 0.001 kJ

To convert Kilojoule to Joule, multiply the value by 1000. To convert Joule back to Kilojoule, divide by 1000.

Example: convert 10 kJ to J:
10 kJ = 10 x 1000 = 10000 J

↔ Convert Joule to Kilojoule

Kilojoule

Definition: A kilojoule (symbol: kJ) is equal to 1000 joules. It's a unit of energy.

History/origin: Based on the joule, using the SI prefix 'kilo-' to denote a factor of one thousand.

Current use: Commonly used to express the energy content of food, fuels, and other substances when the joule would be impractically small. Also used in thermodynamics and other areas of physics and engineering.

Joule

Definition: The joule (symbol: J) is the SI derived unit of energy. It is defined as the energy transferred to (or work done on) an object when a force of one newton acts on that object in the direction of its motion through a distance of one metre (1 newton metre or N⋅m).

History/origin: Named after James Prescott Joule, an English physicist. Joule experimentally determined the mechanical equivalent of heat.

Current use: Used universally in science and engineering to quantify energy, work, and heat. Examples include kinetic energy, potential energy, and heat content of materials.

Kilojoule to Joule Conversion Table

Kilojoule [kJ]Joule [J]
1 kJ1000 J
2 kJ2000 J
5 kJ5000 J
10 kJ10000 J
20 kJ20000 J
50 kJ50000 J
100 kJ100000 J
200 kJ200000 J
500 kJ500000 J
1000 kJ1000000 J

Kilojoule [kJ] to Joule [J] Converter

What is 1 kJ in J?
1 Kilojoule (kJ) equals 1,000 J, and 1 J equals 0.001 kJ.
How do I convert Kilojoule to Joule?
Multiply by 1,000: 10 kJ × 1,000 = 10,000 J. The converter above does it for any value, with the precision you choose.
What is 100 kJ in J?
100 kJ = 100,000 J. Common amounts are listed on this page, each with its own step-by-step page.
Is a Kilojoule bigger than a Joule?
Yes. 1 kJ = 1,000 J, so the same quantity becomes a larger number when written in J.
Kilojoule to Joule Converter | UtilLab