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.
Attojoules to Femtojoules
Convert Attojoule (aJ) to Femtojoule (fJ) instantly with an exact formula, conversion table, and FAQ.
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Convert attojoules (aJ) 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 = aJ × 0.001
Results update instantly for Attojoules to Femtojoules conversions.
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Formula
fJ = aJ × 0.001
aJ = fJ × 1000
Conversion table
| 1 aJ | 0.001000 fJ |
| 5 aJ | 0.005000 fJ |
| 10 aJ | 0.010000 fJ |
| 20 aJ | 0.020000 fJ |
| 50 aJ | 0.050000 fJ |
| 100 aJ | 0.100000 fJ |
| 500 aJ | 0.500000 fJ |
| 1000 aJ | 1 fJ |
Related conversions
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How the formula works
Both attojoule and femtojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in attojoules by 0.001 to get femtojoules. To reverse the conversion, multiply a femtojoule value by 1000 to get back to attojoules.
Frequently asked questions
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.
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 attojoules to femtojoules?
Multiply the attojoule value by 0.001 to get the equivalent in femtojoules. For example, 5 aJ × 0.001 = 0.005000 fJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 0.001 is an exact, non-rounded value.
Can I convert femtojoules back to attojoules?
Yes. Divide the femtojoule value by 0.001, or multiply it by 1000, to get attojoules.
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About converting attojoules to femtojoules
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. 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 attojoules 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.