Nanojoule is 1e-9 joule units.
Nanojoules to Millijoules Converter — nJ to mJ
Convert Nanojoule (nJ) to Millijoule (mJ) using the exact conversion factor (1 nanojoule = 0.000001 millijoule). See the formula, worked examples, and conversion table.
Nanojoules to Millijoules converter
Converter
Energy Converter
Convert joules, calories, kilowatt-hours, BTU, electronvolts, therms, and mechanical work units.
Context values
Some unit families need one extra value for a physically accurate result.
Millijoule is 0.001 joule units.
Result = input x 1e-9 / 0.001.
Energy uses the joule as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Nanojoules to Millijoules
Nanojoule and Millijoule both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Specifically: Nanojoule is 1e-9 joule units, and millijoule is 0.001 joule units.
Formula
millijoules = nanojoules × 0.000001
This factor comes from each unit's defined relationship to the category's base unit: 1 nanojoule equals 1e-9 base units, and 1 millijoule equals 0.001 base units, so dividing one by the other gives the direct nanojoule-to-millijoule factor of 0.000001.
Simple example
1 nJ × 0.000001 = 0.000001 mJ
1 nanojoule = 0.000001 millijoules.
Real-world example
100 nJ × 0.000001 = 0.0001 mJ
100 nanojoules = 0.0001 millijoules.
Conversion table
| Nanojoule (nJ) | Millijoule (mJ) |
|---|---|
| 1 nJ | 0.000001 mJ |
| 10 nJ | 0.00001 mJ |
| 100 nJ | 0.0001 mJ |
| 500 nJ | 0.0005 mJ |
| 1,000 nJ | 0.001 mJ |
| 2,000 nJ | 0.002 mJ |
Reverse conversion: Millijoule to Nanojoule
0.000001 mJ × 1000000 = 1 nJ
0.000001 millijoules = 1 nanojoule.
nanojoules = millijoules × 1000000
For a page dedicated to this direction, see Millijoule to Nanojoule.
Understanding the Nanojoule (nJ)
Nanojoule is 1e-9 joule units.
Understanding the Millijoule (mJ)
Millijoule is 0.001 joule units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many millijoules are in 1 nanojoule?
1 nanojoule equals 0.000001 millijoules, using the exact defined conversion factor rather than an estimate.
How do I convert nanojoule to millijoule?
Multiply the nanojoule value by 0.000001. The converter above does this instantly to whatever precision you set.
How do I convert millijoule back to nanojoule?
Use the reverse factor: 1 millijoule equals 1,000,000 nanojoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a nanojoule?
Nanojoule (nJ) is a unit of energy.
What is a millijoule?
Millijoule (mJ) is a unit of energy.
Is the nanojoule to millijoule conversion exact?
Yes. Both nanojoule and millijoule are defined by fixed standards rather than physical artifacts, so the factor of 0.000001 used above is exact to as many digits as you choose to display.