Millijoule is 0.001 joule units.
Millijoules to Decajoules Converter — mJ to daJ
Convert Millijoule (mJ) to Decajoule (daJ) using the exact conversion factor (1 millijoule = 0.0001 decajoule). See the formula, worked examples, and conversion table.
Millijoules to Decajoules 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.
Decajoule is 10 joule units.
Result = input x 0.001 / 10.
Energy units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Millijoules to Decajoules
Millijoule and Decajoule 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: Millijoule is 0.001 joule units, and decajoule is 10 joule units.
Formula
decajoules = millijoules × 0.0001
This factor comes from each unit's defined relationship to the category's base unit: 1 millijoule equals 0.001 base units, and 1 decajoule equals 10 base units, so dividing one by the other gives the direct millijoule-to-decajoule factor of 0.0001.
Simple example
1 mJ × 0.0001 = 0.0001 daJ
1 millijoule = 0.0001 decajoules.
Real-world example
100 mJ × 0.0001 = 0.01 daJ
100 millijoules = 0.01 decajoules.
Conversion table
| Millijoule (mJ) | Decajoule (daJ) |
|---|---|
| 1 mJ | 0.0001 daJ |
| 10 mJ | 0.001 daJ |
| 50 mJ | 0.005 daJ |
| 100 mJ | 0.01 daJ |
| 500 mJ | 0.05 daJ |
| 1,000 mJ | 0.1 daJ |
Reverse conversion: Decajoule to Millijoule
0.0001 daJ × 10000 = 1 mJ
0.0001 decajoules = 1 millijoule.
millijoules = decajoules × 10000
For a page dedicated to this direction, see Decajoule to Millijoule.
Understanding the Millijoule (mJ)
Millijoule is 0.001 joule units.
Understanding the Decajoule (daJ)
Decajoule is 10 joule units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many decajoules are in 1 millijoule?
1 millijoule equals 0.0001 decajoules, using the exact defined conversion factor rather than an estimate.
How do I convert millijoule to decajoule?
Multiply the millijoule value by 0.0001. The converter above does this instantly to whatever precision you set.
How do I convert decajoule back to millijoule?
Use the reverse factor: 1 decajoule equals 10,000 millijoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a millijoule?
Millijoule (mJ) is a unit of engineering.
What is a decajoule?
Decajoule (daJ) is a unit of engineering.
Is the millijoule to decajoule conversion exact?
Yes. Both millijoule and decajoule are defined by fixed standards rather than physical artifacts, so the factor of 0.0001 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.