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.
Femtojoules to Ronnajoules
Convert Femtojoule (fJ) to Ronnajoule (RJ) instantly with an exact formula, conversion table, and FAQ.
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Convert femtojoules (fJ) to ronnajoules (RJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna prefix.
RJ = fJ × 1.000000000e-42
Results update instantly for Femtojoules to Ronnajoules conversions.
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Formula
RJ = fJ × 1.000000000e-42
fJ = RJ × 1.000000000e+42
Conversion table
| 1 fJ | 1.000000e-42 RJ |
| 5 fJ | 5.000000e-42 RJ |
| 10 fJ | 1.000000e-41 RJ |
| 20 fJ | 2.000000e-41 RJ |
| 50 fJ | 5.000000e-41 RJ |
| 100 fJ | 1.000000e-40 RJ |
| 500 fJ | 5.000000e-40 RJ |
| 1000 fJ | 1.000000e-39 RJ |
Related conversions
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How the formula works
Both femtojoule and ronnajoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in femtojoules by 1.000000000e-42 to get ronnajoules. To reverse the conversion, multiply a ronnajoule value by 1.000000000e+42 to get back to femtojoules.
Frequently asked questions
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.
What is Ronnajoule (RJ)?
A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna prefix.
How do I convert femtojoules to ronnajoules?
Multiply the femtojoule value by 1.000000000e-42 to get the equivalent in ronnajoules. For example, 5 fJ × 1.000000000e-42 = 5.000000e-42 RJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e-42 is an exact, non-rounded value.
Can I convert ronnajoules back to femtojoules?
Yes. Divide the ronnajoule value by 1.000000000e-42, or multiply it by 1.000000000e+42, to get femtojoules.
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About converting femtojoules to ronnajoules
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. A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna prefix.
Use this calculator to move between femtojoules and ronnajoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.