A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
Gigajoules to Zettajoules
Convert Gigajoule (GJ) to Zettajoule (ZJ) instantly with an exact formula, conversion table, and FAQ.
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Convert gigajoules (GJ) to zettajoules (ZJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A zettajoule (ZJ) is a metric-prefixed unit of energy equal to 1021 joules, using the SI zetta prefix.
ZJ = GJ × 1.000000000e-12
Results update instantly for Gigajoules to Zettajoules conversions.
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Formula
ZJ = GJ × 1.000000000e-12
GJ = ZJ × 1000000000000
Conversion table
| 1 GJ | 1.000000e-12 ZJ |
| 5 GJ | 5.000000e-12 ZJ |
| 10 GJ | 1.000000e-11 ZJ |
| 20 GJ | 2.000000e-11 ZJ |
| 50 GJ | 5.000000e-11 ZJ |
| 100 GJ | 1.000000e-10 ZJ |
| 500 GJ | 5.000000e-10 ZJ |
| 1000 GJ | 1.000000e-09 ZJ |
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How the formula works
Both gigajoule and zettajoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in gigajoules by 1.000000000e-12 to get zettajoules. To reverse the conversion, multiply a zettajoule value by 1000000000000 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 Zettajoule (ZJ)?
A zettajoule (ZJ) is a metric-prefixed unit of energy equal to 1021 joules, using the SI zetta prefix.
How do I convert gigajoules to zettajoules?
Multiply the gigajoule value by 1.000000000e-12 to get the equivalent in zettajoules. For example, 5 GJ × 1.000000000e-12 = 5.000000e-12 ZJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.000000000e-12 is an exact, non-rounded value.
Can I convert zettajoules back to gigajoules?
Yes. Divide the zettajoule value by 1.000000000e-12, or multiply it by 1000000000000, to get gigajoules.
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About converting gigajoules to zettajoules
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix. A zettajoule (ZJ) is a metric-prefixed unit of energy equal to 1021 joules, using the SI zetta prefix.
Use this calculator to move between gigajoules and zettajoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.