A rontojoule (rJ) is a metric-prefixed unit of energy equal to 10-27 joules, a fraction of a single joule, using the SI ronto prefix.
Rontojoules to Femtojoules
Convert Rontojoule (rJ) to Femtojoule (fJ) instantly with an exact formula, conversion table, and FAQ.
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Convert rontojoules (rJ) 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 = rJ × 1.000000000e-12
Results update instantly for Rontojoules to Femtojoules conversions.
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Formula
fJ = rJ × 1.000000000e-12
rJ = fJ × 1000000000000
Conversion table
| 1 rJ | 1.000000e-12 fJ |
| 5 rJ | 5.000000e-12 fJ |
| 10 rJ | 1.000000e-11 fJ |
| 20 rJ | 2.000000e-11 fJ |
| 50 rJ | 5.000000e-11 fJ |
| 100 rJ | 1.000000e-10 fJ |
| 500 rJ | 5.000000e-10 fJ |
| 1000 rJ | 1.000000e-09 fJ |
Related conversions
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How the formula works
Both rontojoule and femtojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in rontojoules by 1.000000000e-12 to get femtojoules. To reverse the conversion, multiply a femtojoule value by 1000000000000 to get back to rontojoules.
Frequently asked questions
What is Rontojoule (rJ)?
A rontojoule (rJ) is a metric-prefixed unit of energy equal to 10-27 joules, a fraction of a single joule, using the SI ronto 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 rontojoules to femtojoules?
Multiply the rontojoule value by 1.000000000e-12 to get the equivalent in femtojoules. For example, 5 rJ × 1.000000000e-12 = 5.000000e-12 fJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e-12 is an exact, non-rounded value.
Can I convert femtojoules back to rontojoules?
Yes. Divide the femtojoule value by 1.000000000e-12, or multiply it by 1000000000000, to get rontojoules.
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About converting rontojoules to femtojoules
A rontojoule (rJ) is a metric-prefixed unit of energy equal to 10-27 joules, a fraction of a single joule, using the SI ronto 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 rontojoules 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.