A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
Gigajoules to Femtojoules
Convert Gigajoule (GJ) to Femtojoule (fJ) instantly with an exact formula, conversion table, and FAQ.
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Convert gigajoules (GJ) 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 = GJ × 1.000000000e+24
Results update instantly for Gigajoules to Femtojoules conversions.
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Formula
fJ = GJ × 1.000000000e+24
GJ = fJ × 1.000000000e-24
Conversion table
| 1 GJ | 1.000000e+24 fJ |
| 5 GJ | 5.000000e+24 fJ |
| 10 GJ | 1.000000e+25 fJ |
| 20 GJ | 2.000000e+25 fJ |
| 50 GJ | 5.000000e+25 fJ |
| 100 GJ | 1.000000e+26 fJ |
| 500 GJ | 5.000000e+26 fJ |
| 1000 GJ | 1.000000e+27 fJ |
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How the formula works
Both gigajoule and femtojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in gigajoules by 1.000000000e+24 to get femtojoules. To reverse the conversion, multiply a femtojoule value by 1.000000000e-24 to get back to gigajoules.
Frequently asked questions
What is Gigajoule (GJ)?
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga 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 gigajoules to femtojoules?
Multiply the gigajoule value by 1.000000000e+24 to get the equivalent in femtojoules. For example, 5 GJ × 1.000000000e+24 = 5.000000e+24 fJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e+24 is an exact, non-rounded value.
Can I convert femtojoules back to gigajoules?
Yes. Divide the femtojoule value by 1.000000000e+24, or multiply it by 1.000000000e-24, to get gigajoules.
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About converting gigajoules to femtojoules
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga 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 gigajoules 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.