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.
Millijoules to Yoctojoules
Convert Millijoule (mJ) to Yoctojoule (yJ) instantly with an exact formula, conversion table, and FAQ.
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Convert millijoules (mJ) to yoctojoules (yJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A yoctojoule (yJ) is a metric-prefixed unit of energy equal to 10-24 joules, a fraction of a single joule, using the SI yocto prefix.
yJ = mJ × 1.000000000e+21
Results update instantly for Millijoules to Yoctojoules conversions.
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Formula
yJ = mJ × 1.000000000e+21
mJ = yJ × 1.000000000e-21
Conversion table
| 1 mJ | 1.000000e+21 yJ |
| 5 mJ | 5.000000e+21 yJ |
| 10 mJ | 1.000000e+22 yJ |
| 20 mJ | 2.000000e+22 yJ |
| 50 mJ | 5.000000e+22 yJ |
| 100 mJ | 1.000000e+23 yJ |
| 500 mJ | 5.000000e+23 yJ |
| 1000 mJ | 1.000000e+24 yJ |
Related conversions
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How the formula works
Both millijoule and yoctojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in millijoules by 1.000000000e+21 to get yoctojoules. To reverse the conversion, multiply a yoctojoule value by 1.000000000e-21 to get back to millijoules.
Frequently asked questions
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.
What is Yoctojoule (yJ)?
A yoctojoule (yJ) is a metric-prefixed unit of energy equal to 10-24 joules, a fraction of a single joule, using the SI yocto prefix.
How do I convert millijoules to yoctojoules?
Multiply the millijoule value by 1.000000000e+21 to get the equivalent in yoctojoules. For example, 5 mJ × 1.000000000e+21 = 5.000000e+21 yJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e+21 is an exact, non-rounded value.
Can I convert yoctojoules back to millijoules?
Yes. Divide the yoctojoule value by 1.000000000e+21, or multiply it by 1.000000000e-21, to get millijoules.
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About converting millijoules to yoctojoules
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. A yoctojoule (yJ) is a metric-prefixed unit of energy equal to 10-24 joules, a fraction of a single joule, using the SI yocto prefix.
Use this calculator to move between millijoules and yoctojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.