A microjoule (uJ) is a metric-prefixed unit of energy equal to 10-6 joules, a fraction of a single joule, using the SI micro prefix.
Microjoules to Femtojoules
Convert Microjoule (uJ) to Femtojoule (fJ) instantly with an exact formula, conversion table, and FAQ.
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Convert microjoules (uJ) to femtojoules (fJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A femtojoule (fJ) is a metric-prefixed unit of energy equal to 10-15 joules, a fraction of a single joule, using the SI femto prefix.
fJ = uJ × 1000000000
Results update instantly for Microjoules to Femtojoules conversions.
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Formula
fJ = uJ × 1000000000
uJ = fJ × 1.000000000e-09
Conversion table
| 1 uJ | 1.000000e+09 fJ |
| 5 uJ | 5.000000e+09 fJ |
| 10 uJ | 1.000000e+10 fJ |
| 20 uJ | 2.000000e+10 fJ |
| 50 uJ | 5.000000e+10 fJ |
| 100 uJ | 1.000000e+11 fJ |
| 500 uJ | 5.000000e+11 fJ |
| 1000 uJ | 1.000000e+12 fJ |
Related conversions
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How the formula works
Both microjoule and femtojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in microjoules by 1000000000 to get femtojoules. To reverse the conversion, multiply a femtojoule value by 1.000000000e-09 to get back to microjoules.
Frequently asked questions
What is Microjoule (uJ)?
A microjoule (uJ) is a metric-prefixed unit of energy equal to 10-6 joules, a fraction of a single joule, using the SI micro prefix.
What is Femtojoule (fJ)?
A femtojoule (fJ) is a metric-prefixed unit of energy equal to 10-15 joules, a fraction of a single joule, using the SI femto prefix.
How do I convert microjoules to femtojoules?
Multiply the microjoule value by 1000000000 to get the equivalent in femtojoules. For example, 5 uJ × 1000000000 = 5.000000e+09 fJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1000000000 is an exact, non-rounded value.
Can I convert femtojoules back to microjoules?
Yes. Divide the femtojoule value by 1000000000, or multiply it by 1.000000000e-09, to get microjoules.
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About converting microjoules to femtojoules
A microjoule (uJ) is a metric-prefixed unit of energy equal to 10-6 joules, a fraction of a single joule, using the SI micro prefix. A femtojoule (fJ) is a metric-prefixed unit of energy equal to 10-15 joules, a fraction of a single joule, using the SI femto prefix.
Use this calculator to move between microjoules and femtojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.