Energy Converter

Convert between chemical, electrical and physical energy units.

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Related Conversions
1 J to kJ 10 J to kJ 50 J to kJ 1,000 J to kJ 2,500 J to kJ 8,000 J to kJ 11,000 J to kJ 20,000 J to kJ 24,000 J to kJ 50,000 J to kJ 100,000 J to kJ 200,000 J to kJ
Reverse Conversions
5 kJ to J 10 kJ to J 50 kJ to J 500 kJ to J 1,000 kJ to J 5,000 kJ to J 9,000 kJ to J 12,000 kJ to J 24,000 kJ to J 40,000 kJ to J 50,000 kJ to J 200,000 kJ to J
More Energy Conversions
1 GJ to kWh 1 GJ to MJ 1 MJ to BTU 100 J to cal 1 MJ to kWh 2 GJ to MJ 2 MJ to BTU 100 kJ to kcal 1 kWh to cal 10,000 J to kJ

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Popular Conversions

Kilowatt-Hours to Megajoules Megajoules to Kilowatt-Hours Joules to Calories Kilocalories to Kilojoules British Thermal Units to Joules Watt-Hours to Joules

Common Benchmarks

100 W bulb for 1 hour 0.1 kWh
Match stick 1 kJ
Food calorie 4184 J
Slice of bread 330 kJ
Phone battery 40 kJ
1 kWh 3.6 MJ

Formula

kJ = J × 0.001

Example

Example: convert 10000 joules to kilojoules.

10000 J = 10 kJ

Conversion table

joules (J) kilojoules (kJ)
1 J 0.001 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

Explanation

These are both units.

How to convert joules to kilojoules

  1. Start with the value in joules (J).
  2. Multiply it by 0.001.
  3. The result is the measurement in kilojoules (kJ).

Example: 10000 J → 10 kJ

Frequently Asked Questions

How much is 10000 joules in kilojoules?

10000 joules equals 10 kilojoules.

How many kilojoules is 1 joule?

1 joule equals 0.001 kilojoules.

How many joules is 1 kilojoule?

1 kilojoule equals 1000 joules.

What is the difference between joules and kilojoules?

Both measure energy in SI. The main difference is usually scale: some units are convenient for smaller values, while others are used to express larger values more practically.

Where are joules and kilojoules used?

They are used in physics and engineering to measure work, energy, and heat; the most practical unit depends on the magnitude.

Why does 1 joule equal 0.001 kilojoules?

Because the “kilo-” prefix means 1000. One kilojoule equals 1000 joules, so 1 joule corresponds to 0.001 kilojoules.