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 Quectojoules
Convert Femtojoule (fJ) to Quectojoule (qJ) instantly with an exact formula, conversion table, and FAQ.
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Convert femtojoules (fJ) to quectojoules (qJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A quectojoule (qJ) is a metric-prefixed unit of energy equal to 10-30 joules, a fraction of a single joule, using the SI quecto prefix.
qJ = fJ × 1.000000000e+15
Results update instantly for Femtojoules to Quectojoules conversions.
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Formula
qJ = fJ × 1.000000000e+15
fJ = qJ × 1.000000000e-15
Conversion table
| 1 fJ | 1.000000e+15 qJ |
| 5 fJ | 5.000000e+15 qJ |
| 10 fJ | 1.000000e+16 qJ |
| 20 fJ | 2.000000e+16 qJ |
| 50 fJ | 5.000000e+16 qJ |
| 100 fJ | 1.000000e+17 qJ |
| 500 fJ | 5.000000e+17 qJ |
| 1000 fJ | 1.000000e+18 qJ |
Related conversions
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How the formula works
Both femtojoule and quectojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in femtojoules by 1.000000000e+15 to get quectojoules. To reverse the conversion, multiply a quectojoule value by 1.000000000e-15 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 Quectojoule (qJ)?
A quectojoule (qJ) is a metric-prefixed unit of energy equal to 10-30 joules, a fraction of a single joule, using the SI quecto prefix.
How do I convert femtojoules to quectojoules?
Multiply the femtojoule value by 1.000000000e+15 to get the equivalent in quectojoules. For example, 5 fJ × 1.000000000e+15 = 5.000000e+15 qJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e+15 is an exact, non-rounded value.
Can I convert quectojoules back to femtojoules?
Yes. Divide the quectojoule value by 1.000000000e+15, or multiply it by 1.000000000e-15, to get femtojoules.
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About converting femtojoules to quectojoules
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 quectojoule (qJ) is a metric-prefixed unit of energy equal to 10-30 joules, a fraction of a single joule, using the SI quecto prefix.
Use this calculator to move between femtojoules and quectojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.