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 Ergs
Convert Femtojoule (fJ) to Erg (erg) instantly with an exact formula, conversion table, and FAQ.
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Convert femtojoules (fJ) to ergs (erg) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
An erg is the CGS (centimeter-gram-second) unit of energy, equal to one ten-millionth of a joule.
erg = fJ × 1.000000000e-08
Results update instantly for Femtojoules to Ergs conversions.
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Formula
erg = fJ × 1.000000000e-08
fJ = erg × 100000000
Conversion table
| 1 fJ | 1.000000e-08 erg |
| 5 fJ | 5.000000e-08 erg |
| 10 fJ | 1.000000e-07 erg |
| 20 fJ | 2.000000e-07 erg |
| 50 fJ | 5.000000e-07 erg |
| 100 fJ | 0.000001 erg |
| 500 fJ | 0.000005 erg |
| 1000 fJ | 0.000010 erg |
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How the formula works
Both femtojoule and erg measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in femtojoules by 1.000000000e-08 to get ergs. To reverse the conversion, multiply a erg value by 100000000 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 Erg (erg)?
An erg is the CGS (centimeter-gram-second) unit of energy, equal to one ten-millionth of a joule.
How do I convert femtojoules to ergs?
Multiply the femtojoule value by 1.000000000e-08 to get the equivalent in ergs. For example, 5 fJ × 1.000000000e-08 = 5.000000e-08 erg.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e-08 is an exact, non-rounded value.
Can I convert ergs back to femtojoules?
Yes. Divide the erg value by 1.000000000e-08, or multiply it by 100000000, to get femtojoules.
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About converting femtojoules to ergs
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. An erg is the CGS (centimeter-gram-second) unit of energy, equal to one ten-millionth of a joule.
Use this calculator to move between femtojoules and ergs accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.