Terajoule is 1000000000000 joule units.
Terajoules to Millijoules Converter — TJ to mJ
Convert Terajoule (TJ) to Millijoule (mJ) using the exact conversion factor (1 terajoule = 1e+15 millijoule). See the formula, worked examples, and conversion table.
Terajoules 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+12 / 0.001.
Energy uses the joule as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Terajoules to Millijoules
Terajoule and Millijoule both measure energy, and the conversion is especially useful for comparing nutrition labels (kilocalories) against scientific energy figures (joules). Specifically: Terajoule is 1000000000000 joule units, and millijoule is 0.001 joule units.
Formula
millijoules = terajoules × 1e+15
This factor comes from each unit's defined relationship to the category's base unit: 1 terajoule equals 1e+12 base units, and 1 millijoule equals 0.001 base units, so dividing one by the other gives the direct terajoule-to-millijoule factor of 1e+15.
Simple example
1 TJ × 1e+15 = 1e+15 mJ
1 terajoule = 1e+15 millijoules.
Real-world example
100 TJ × 1e+15 = 1e+17 mJ
100 terajoules = 1e+17 millijoules.
Conversion table
| Terajoule (TJ) | Millijoule (mJ) |
|---|---|
| 1 TJ | 1e+15 mJ |
| 10 TJ | 1e+16 mJ |
| 100 TJ | 1e+17 mJ |
| 500 TJ | 5e+17 mJ |
| 1,000 TJ | 1e+18 mJ |
| 2,000 TJ | 2e+18 mJ |
Reverse conversion: Millijoule to Terajoule
1e+15 mJ × 1e-15 = 1 TJ
1e+15 millijoules = 1 terajoule.
terajoules = millijoules × 1e-15
For a page dedicated to this direction, see Millijoule to Terajoule.
Understanding the Terajoule (TJ)
Terajoule is 1000000000000 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 terajoule?
1 terajoule equals 1e+15 millijoules, using the exact defined conversion factor rather than an estimate.
How do I convert terajoule to millijoule?
Multiply the terajoule value by 1e+15. The converter above does this instantly to whatever precision you set.
How do I convert millijoule back to terajoule?
Use the reverse factor: 1 millijoule equals 1e-15 terajoules. You can also use the swap control in the converter above to flip the direction instantly.
What is a terajoule?
Terajoule (TJ) is a unit of energy.
What is a millijoule?
Millijoule (mJ) is a unit of energy.
Is the terajoule to millijoule conversion exact?
Yes. Both terajoule and millijoule are defined by fixed standards rather than physical artifacts, so the factor of 1e+15 used above is exact to as many digits as you choose to display.