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 Zeptojoules
Convert Attojoule (aJ) to Zeptojoule (zJ) instantly with an exact formula, conversion table, and FAQ.
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Convert attojoules (aJ) to zeptojoules (zJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A zeptojoule (zJ) is a metric-prefixed unit of energy equal to 10-21 joules, a fraction of a single joule, using the SI zepto prefix.
zJ = aJ × 1000
Results update instantly for Attojoules to Zeptojoules conversions.
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Formula
zJ = aJ × 1000
aJ = zJ × 0.001
Conversion table
| 1 aJ | 1000 zJ |
| 5 aJ | 5000 zJ |
| 10 aJ | 10000 zJ |
| 20 aJ | 20000 zJ |
| 50 aJ | 50000 zJ |
| 100 aJ | 100000 zJ |
| 500 aJ | 500000 zJ |
| 1000 aJ | 1.000000e+06 zJ |
Related conversions
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How the formula works
Both attojoule and zeptojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in attojoules by 1000 to get zeptojoules. To reverse the conversion, multiply a zeptojoule value by 0.001 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 Zeptojoule (zJ)?
A zeptojoule (zJ) is a metric-prefixed unit of energy equal to 10-21 joules, a fraction of a single joule, using the SI zepto prefix.
How do I convert attojoules to zeptojoules?
Multiply the attojoule value by 1000 to get the equivalent in zeptojoules. For example, 5 aJ × 1000 = 5000 zJ.
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 zeptojoules back to attojoules?
Yes. Divide the zeptojoule value by 1000, or multiply it by 0.001, to get attojoules.
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About converting attojoules to zeptojoules
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 zeptojoule (zJ) is a metric-prefixed unit of energy equal to 10-21 joules, a fraction of a single joule, using the SI zepto prefix.
Use this calculator to move between attojoules and zeptojoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.