A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
Gigajoules to Attojoules
Convert Gigajoule (GJ) to Attojoule (aJ) instantly with an exact formula, conversion table, and FAQ.
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Convert gigajoules (GJ) 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 = GJ × 1.000000000e+27
Results update instantly for Gigajoules to Attojoules conversions.
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Formula
aJ = GJ × 1.000000000e+27
GJ = aJ × 1.000000000e-27
Conversion table
| 1 GJ | 1.000000e+27 aJ |
| 5 GJ | 5.000000e+27 aJ |
| 10 GJ | 1.000000e+28 aJ |
| 20 GJ | 2.000000e+28 aJ |
| 50 GJ | 5.000000e+28 aJ |
| 100 GJ | 1.000000e+29 aJ |
| 500 GJ | 5.000000e+29 aJ |
| 1000 GJ | 1.000000e+30 aJ |
Related conversions
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How the formula works
Both gigajoule and attojoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in gigajoules by 1.000000000e+27 to get attojoules. To reverse the conversion, multiply a attojoule value by 1.000000000e-27 to get back to gigajoules.
Frequently asked questions
What is Gigajoule (GJ)?
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga 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 gigajoules to attojoules?
Multiply the gigajoule value by 1.000000000e+27 to get the equivalent in attojoules. For example, 5 GJ × 1.000000000e+27 = 5.000000e+27 aJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e+27 is an exact, non-rounded value.
Can I convert attojoules back to gigajoules?
Yes. Divide the attojoule value by 1.000000000e+27, or multiply it by 1.000000000e-27, to get gigajoules.
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About converting gigajoules to attojoules
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga 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 gigajoules 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.