A attojoule (aJ) is a metric-prefixed unit of energy equal to 10-18 joules, a fraction of a single joule, using the SI atto prefix.
Attojoules to Millijoules
Convert Attojoule (aJ) to Millijoule (mJ) instantly with an exact formula, conversion table, and FAQ.
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Convert attojoules (aJ) 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 = aJ × 1.000000000e-15
Results update instantly for Attojoules to Millijoules conversions.
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Formula
mJ = aJ × 1.000000000e-15
aJ = mJ × 1.000000000e+15
Conversion table
| 1 aJ | 1.000000e-15 mJ |
| 5 aJ | 5.000000e-15 mJ |
| 10 aJ | 1.000000e-14 mJ |
| 20 aJ | 2.000000e-14 mJ |
| 50 aJ | 5.000000e-14 mJ |
| 100 aJ | 1.000000e-13 mJ |
| 500 aJ | 5.000000e-13 mJ |
| 1000 aJ | 1.000000e-12 mJ |
Related conversions
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How the formula works
Both attojoule and millijoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in attojoules by 1.000000000e-15 to get millijoules. To reverse the conversion, multiply a millijoule value by 1.000000000e+15 to get back to attojoules.
Frequently asked questions
What is Attojoule (aJ)?
A attojoule (aJ) is a metric-prefixed unit of energy equal to 10-18 joules, a fraction of a single joule, using the SI atto 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 attojoules to millijoules?
Multiply the attojoule value by 1.000000000e-15 to get the equivalent in millijoules. For example, 5 aJ × 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 attojoules?
Yes. Divide the millijoule value by 1.000000000e-15, or multiply it by 1.000000000e+15, to get attojoules.
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About converting attojoules to millijoules
A attojoule (aJ) is a metric-prefixed unit of energy equal to 10-18 joules, a fraction of a single joule, using the SI atto 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 attojoules 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.