A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
Gigajoules to Btu
Convert Gigajoule (GJ) to British thermal unit (BTU) instantly with an exact formula, conversion table, and FAQ.
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Convert gigajoules (GJ) to btu (BTU) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
The British thermal unit (BTU) is the energy needed to raise one pound of water by one degree Fahrenheit, widely used for heating and air-conditioning ratings.
BTU = GJ × 947817.1203
Results update instantly for Gigajoules to Btu conversions.
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Formula
BTU = GJ × 947817.1203
GJ = BTU × 0.000001055055853
Conversion table
| 1 GJ | 947817.120313 BTU |
| 5 GJ | 4.739086e+06 BTU |
| 10 GJ | 9.478171e+06 BTU |
| 20 GJ | 1.895634e+07 BTU |
| 50 GJ | 4.739086e+07 BTU |
| 100 GJ | 9.478171e+07 BTU |
| 500 GJ | 4.739086e+08 BTU |
| 1000 GJ | 9.478171e+08 BTU |
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How the formula works
Both gigajoule and british thermal unit measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in gigajoules by 947817.1203 to get btu. To reverse the conversion, multiply a british thermal unit value by 0.000001055055853 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 British thermal unit (BTU)?
The British thermal unit (BTU) is the energy needed to raise one pound of water by one degree Fahrenheit, widely used for heating and air-conditioning ratings.
How do I convert gigajoules to btu?
Multiply the gigajoule value by 947817.1203 to get the equivalent in btu. For example, 5 GJ × 947817.1203 = 4.739086e+06 BTU.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 947817.1203 is an exact, non-rounded value.
Can I convert btu back to gigajoules?
Yes. Divide the british thermal unit value by 947817.1203, or multiply it by 0.000001055055853, to get gigajoules.
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About converting gigajoules to btu
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix. The British thermal unit (BTU) is the energy needed to raise one pound of water by one degree Fahrenheit, widely used for heating and air-conditioning ratings.
Use this calculator to move between gigajoules and btu accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.