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 to Gigajoules
Convert British thermal unit (BTU) to Gigajoule (GJ) instantly with an exact formula, conversion table, and FAQ.
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Convert btu (BTU) to gigajoules (GJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
GJ = BTU × 0.000001055055853
Results update instantly for Btu to Gigajoules conversions.
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Formula
GJ = BTU × 0.000001055055853
BTU = GJ × 947817.1203
Conversion table
| 1 BTU | 0.000001 GJ |
| 5 BTU | 0.000005 GJ |
| 10 BTU | 0.000011 GJ |
| 20 BTU | 0.000021 GJ |
| 50 BTU | 0.000053 GJ |
| 100 BTU | 0.000106 GJ |
| 500 BTU | 0.000528 GJ |
| 1000 BTU | 0.001055 GJ |
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How the formula works
Both british thermal unit and gigajoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in btu by 0.000001055055853 to get gigajoules. To reverse the conversion, multiply a gigajoule value by 947817.1203 to get back to btu.
Frequently asked questions
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.
What is Gigajoule (GJ)?
A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
How do I convert btu to gigajoules?
Multiply the british thermal unit value by 0.000001055055853 to get the equivalent in gigajoules. For example, 5 BTU × 0.000001055055853 = 0.000005 GJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 0.000001055055853 is an exact, non-rounded value.
Can I convert gigajoules back to btu?
Yes. Divide the gigajoule value by 0.000001055055853, or multiply it by 947817.1203, to get btu.
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About converting btu to gigajoules
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. A gigajoule (GJ) is a metric-prefixed unit of energy equal to 109 joules, using the SI giga prefix.
Use this calculator to move between btu and gigajoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.