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 Attojoules
Convert Femtojoule (fJ) to Attojoule (aJ) instantly with an exact formula, conversion table, and FAQ.
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Convert femtojoules (fJ) to attojoules (aJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A attojoule (aJ) is a metric-prefixed unit of energy equal to 10-18 joules, a fraction of a single joule, using the SI atto prefix.
aJ = fJ × 1000
Results update instantly for Femtojoules to Attojoules conversions.
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Formula
aJ = fJ × 1000
fJ = aJ × 0.001
Conversion table
| 1 fJ | 1000 aJ |
| 5 fJ | 5000 aJ |
| 10 fJ | 10000 aJ |
| 20 fJ | 20000 aJ |
| 50 fJ | 50000 aJ |
| 100 fJ | 100000 aJ |
| 500 fJ | 500000 aJ |
| 1000 fJ | 1.000000e+06 aJ |
Related conversions
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How the formula works
Both femtojoule and attojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in femtojoules by 1000 to get attojoules. To reverse the conversion, multiply a attojoule value by 0.001 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 Attojoule (aJ)?
A attojoule (aJ) is a metric-prefixed unit of energy equal to 10-18 joules, a fraction of a single joule, using the SI atto prefix.
How do I convert femtojoules to attojoules?
Multiply the femtojoule value by 1000 to get the equivalent in attojoules. For example, 5 fJ × 1000 = 5000 aJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1000 is an exact, non-rounded value.
Can I convert attojoules back to femtojoules?
Yes. Divide the attojoule value by 1000, or multiply it by 0.001, to get femtojoules.
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About converting femtojoules to attojoules
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 attojoule (aJ) is a metric-prefixed unit of energy equal to 10-18 joules, a fraction of a single joule, using the SI atto prefix.
Use this calculator to move between femtojoules and attojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.