A terajoule (TJ) is a metric-prefixed unit of energy equal to 1012 joules, using the SI tera prefix.
Terajoules to Millijoules
Convert Terajoule (TJ) to Millijoule (mJ) instantly with an exact formula, conversion table, and FAQ.
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Convert terajoules (TJ) to millijoules (mJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
mJ = TJ × 1.000000000e+15
Results update instantly for Terajoules to Millijoules conversions.
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Formula
mJ = TJ × 1.000000000e+15
TJ = mJ × 1.000000000e-15
Conversion table
| 1 TJ | 1.000000e+15 mJ |
| 5 TJ | 5.000000e+15 mJ |
| 10 TJ | 1.000000e+16 mJ |
| 20 TJ | 2.000000e+16 mJ |
| 50 TJ | 5.000000e+16 mJ |
| 100 TJ | 1.000000e+17 mJ |
| 500 TJ | 5.000000e+17 mJ |
| 1000 TJ | 1.000000e+18 mJ |
Related conversions
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How the formula works
Both terajoule and millijoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in terajoules by 1.000000000e+15 to get millijoules. To reverse the conversion, multiply a millijoule value by 1.000000000e-15 to get back to terajoules.
Frequently asked questions
What is Terajoule (TJ)?
A terajoule (TJ) is a metric-prefixed unit of energy equal to 1012 joules, using the SI tera prefix.
What is Millijoule (mJ)?
A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
How do I convert terajoules to millijoules?
Multiply the terajoule value by 1.000000000e+15 to get the equivalent in millijoules. For example, 5 TJ × 1.000000000e+15 = 5.000000e+15 mJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e+15 is an exact, non-rounded value.
Can I convert millijoules back to terajoules?
Yes. Divide the millijoule value by 1.000000000e+15, or multiply it by 1.000000000e-15, to get terajoules.
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About converting terajoules to millijoules
A terajoule (TJ) is a metric-prefixed unit of energy equal to 1012 joules, using the SI tera prefix. A millijoule (mJ) is a metric-prefixed unit of energy equal to 10-3 joules, a fraction of a single joule, using the SI milli prefix.
Use this calculator to move between terajoules and millijoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.