An erg is the CGS (centimeter-gram-second) unit of energy, equal to one ten-millionth of a joule.
Ergs to Femtojoules
Convert Erg (erg) to Femtojoule (fJ) instantly with an exact formula, conversion table, and FAQ.
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Convert ergs (erg) 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 = erg × 100000000
Results update instantly for Ergs to Femtojoules conversions.
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Formula
fJ = erg × 100000000
erg = fJ × 1.000000000e-08
Conversion table
| 1 erg | 1.000000e+08 fJ |
| 5 erg | 5.000000e+08 fJ |
| 10 erg | 1.000000e+09 fJ |
| 20 erg | 2.000000e+09 fJ |
| 50 erg | 5.000000e+09 fJ |
| 100 erg | 1.000000e+10 fJ |
| 500 erg | 5.000000e+10 fJ |
| 1000 erg | 1.000000e+11 fJ |
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How the formula works
Both erg and femtojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in ergs by 100000000 to get femtojoules. To reverse the conversion, multiply a femtojoule value by 1.000000000e-08 to get back to ergs.
Frequently asked questions
What is Erg (erg)?
An erg is the CGS (centimeter-gram-second) unit of energy, equal to one ten-millionth of a joule.
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 ergs to femtojoules?
Multiply the erg value by 100000000 to get the equivalent in femtojoules. For example, 5 erg × 100000000 = 5.000000e+08 fJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 100000000 is an exact, non-rounded value.
Can I convert femtojoules back to ergs?
Yes. Divide the femtojoule value by 100000000, or multiply it by 1.000000000e-08, to get ergs.
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About converting ergs to femtojoules
An erg is the CGS (centimeter-gram-second) unit of energy, equal to one ten-millionth of a joule. 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 ergs 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.