Megajoule is 1000000 joule units.
Megajoules to Kilojoules Converter — MJ to kJ
Convert Megajoule (MJ) to Kilojoule (kJ) using the exact conversion factor (1 megajoule = 1,000 kilojoule). See the formula, worked examples, and conversion table.
Megajoules to Kilojoules converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
Context values
Some unit families need one extra value for a physically accurate result.
Kilojoule is 1000 joule units.
Result = input x 1e+6 / 1000.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Megajoules to Kilojoules
Megajoule and Kilojoule both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Specifically: Megajoule is 1000000 joule units, and kilojoule is 1000 joule units.
Formula
kilojoules = megajoules × 1000
This factor comes from each unit's defined relationship to the category's base unit: 1 megajoule equals 1000000 base units, and 1 kilojoule equals 1000 base units, so dividing one by the other gives the direct megajoule-to-kilojoule factor of 1000.
Simple example
1 MJ × 1000 = 1,000 kJ
1 megajoule = 1,000 kilojoules.
Real-world example
100 MJ × 1000 = 100,000 kJ
100 megajoules = 100,000 kilojoules.
Conversion table
| Megajoule (MJ) | Kilojoule (kJ) |
|---|---|
| 1 MJ | 1,000 kJ |
| 10 MJ | 10,000 kJ |
| 50 MJ | 50,000 kJ |
| 100 MJ | 100,000 kJ |
| 500 MJ | 500,000 kJ |
| 1,000 MJ | 1,000,000 kJ |
Reverse conversion: Kilojoule to Megajoule
1 kJ × 0.001 = 0.001 MJ
1 kilojoule = 0.001 megajoules.
megajoules = kilojoules × 0.001
For a page dedicated to this direction, see Kilojoule to Megajoule.
Understanding the Megajoule (MJ)
Megajoule is 1000000 joule units.
Understanding the Kilojoule (kJ)
Kilojoule is 1000 joule units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilojoules are in 1 megajoule?
1 megajoule equals 1,000 kilojoules, using the exact defined conversion factor rather than an estimate.
How do I convert megajoule to kilojoule?
Multiply the megajoule value by 1000. The converter above does this instantly to whatever precision you set.
How do I convert kilojoule back to megajoule?
Use the reverse factor: 1 kilojoule equals 0.001 megajoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a megajoule?
Megajoule (MJ) is a unit of engineering.
What is a kilojoule?
Kilojoule (kJ) is a unit of engineering.
Is the megajoule to kilojoule conversion exact?
Yes. Both megajoule and kilojoule are defined by fixed standards rather than physical artifacts, so the factor of 1000 used above is exact to as many digits as you choose to display.
Why do engineering unit conventions vary so much by region and industry?
Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.