A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
Gigajoules to Terajoules
Convert Gigajoule (GJ) to Terajoule (TJ) instantly with an exact formula, conversion table, and FAQ.
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Convert gigajoules (GJ) to terajoules (TJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A terajoule (TJ) is a metric-prefixed unit of energy equal to 1012 joules, using the SI tera prefix.
TJ = GJ × 0.001
Results update instantly for Gigajoules to Terajoules conversions.
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Formula
TJ = GJ × 0.001
GJ = TJ × 1000
Conversion table
| 1 GJ | 0.001000 TJ |
| 5 GJ | 0.005000 TJ |
| 10 GJ | 0.010000 TJ |
| 20 GJ | 0.020000 TJ |
| 50 GJ | 0.050000 TJ |
| 100 GJ | 0.100000 TJ |
| 500 GJ | 0.500000 TJ |
| 1000 GJ | 1 TJ |
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How the formula works
Both gigajoule and terajoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in gigajoules by 0.001 to get terajoules. To reverse the conversion, multiply a terajoule value by 1000 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 Terajoule (TJ)?
A terajoule (TJ) is a metric-prefixed unit of energy equal to 1012 joules, using the SI tera prefix.
How do I convert gigajoules to terajoules?
Multiply the gigajoule value by 0.001 to get the equivalent in terajoules. For example, 5 GJ × 0.001 = 0.005000 TJ.
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 terajoules back to gigajoules?
Yes. Divide the terajoule value by 0.001, or multiply it by 1000, to get gigajoules.
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About converting gigajoules to terajoules
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix. A terajoule (TJ) is a metric-prefixed unit of energy equal to 1012 joules, using the SI tera prefix.
Use this calculator to move between gigajoules and terajoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.