A zettajoule (ZJ) is a metric-prefixed unit of energy equal to 1021 joules, using the SI zetta prefix.
Zettajoules to Attojoules
Convert Zettajoule (ZJ) to Attojoule (aJ) instantly with an exact formula, conversion table, and FAQ.
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Convert zettajoules (ZJ) 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 = ZJ × 1.000000000e+39
Results update instantly for Zettajoules to Attojoules conversions.
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Formula
aJ = ZJ × 1.000000000e+39
ZJ = aJ × 1.000000000e-39
Conversion table
| 1 ZJ | 1.000000e+39 aJ |
| 5 ZJ | 5.000000e+39 aJ |
| 10 ZJ | 1.000000e+40 aJ |
| 20 ZJ | 2.000000e+40 aJ |
| 50 ZJ | 5.000000e+40 aJ |
| 100 ZJ | 1.000000e+41 aJ |
| 500 ZJ | 5.000000e+41 aJ |
| 1000 ZJ | 1.000000e+42 aJ |
Related conversions
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How the formula works
Both zettajoule and attojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in zettajoules by 1.000000000e+39 to get attojoules. To reverse the conversion, multiply a attojoule value by 1.000000000e-39 to get back to zettajoules.
Frequently asked questions
What is Zettajoule (ZJ)?
A zettajoule (ZJ) is a metric-prefixed unit of energy equal to 1021 joules, using the SI zetta 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 zettajoules to attojoules?
Multiply the zettajoule value by 1.000000000e+39 to get the equivalent in attojoules. For example, 5 ZJ × 1.000000000e+39 = 5.000000e+39 aJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e+39 is an exact, non-rounded value.
Can I convert attojoules back to zettajoules?
Yes. Divide the attojoule value by 1.000000000e+39, or multiply it by 1.000000000e-39, to get zettajoules.
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About converting zettajoules to attojoules
A zettajoule (ZJ) is a metric-prefixed unit of energy equal to 1021 joules, using the SI zetta 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 zettajoules 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.