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 Decijoules
Convert Millijoule (mJ) to Decijoule (dJ) instantly with an exact formula, conversion table, and FAQ.
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Convert millijoules (mJ) to decijoules (dJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A decijoule (dJ) is a metric-prefixed unit of energy equal to 10-1 joules, a fraction of a single joule, using the SI deci prefix.
dJ = mJ × 0.01
Results update instantly for Millijoules to Decijoules conversions.
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Formula
dJ = mJ × 0.01
mJ = dJ × 100
Conversion table
| 1 mJ | 0.010000 dJ |
| 5 mJ | 0.050000 dJ |
| 10 mJ | 0.100000 dJ |
| 20 mJ | 0.200000 dJ |
| 50 mJ | 0.500000 dJ |
| 100 mJ | 1 dJ |
| 500 mJ | 5 dJ |
| 1000 mJ | 10 dJ |
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How the formula works
Both millijoule and decijoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in millijoules by 0.01 to get decijoules. To reverse the conversion, multiply a decijoule value by 100 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 Decijoule (dJ)?
A decijoule (dJ) is a metric-prefixed unit of energy equal to 10-1 joules, a fraction of a single joule, using the SI deci prefix.
How do I convert millijoules to decijoules?
Multiply the millijoule value by 0.01 to get the equivalent in decijoules. For example, 5 mJ × 0.01 = 0.050000 dJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 0.01 is an exact, non-rounded value.
Can I convert decijoules back to millijoules?
Yes. Divide the decijoule value by 0.01, or multiply it by 100, to get millijoules.
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About converting millijoules to decijoules
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 decijoule (dJ) is a metric-prefixed unit of energy equal to 10-1 joules, a fraction of a single joule, using the SI deci prefix.
Use this calculator to move between millijoules and decijoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.