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 Ronnajoules
Convert British thermal unit (BTU) to Ronnajoule (RJ) instantly with an exact formula, conversion table, and FAQ.
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Convert btu (BTU) to ronnajoules (RJ) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna prefix.
RJ = BTU × 1.055055853e-24
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Formula
RJ = BTU × 1.055055853e-24
BTU = RJ × 9.478171203e+23
Conversion table
| 1 BTU | 1.055056e-24 RJ |
| 5 BTU | 5.275279e-24 RJ |
| 10 BTU | 1.055056e-23 RJ |
| 20 BTU | 2.110112e-23 RJ |
| 50 BTU | 5.275279e-23 RJ |
| 100 BTU | 1.055056e-22 RJ |
| 500 BTU | 5.275279e-22 RJ |
| 1000 BTU | 1.055056e-21 RJ |
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How the formula works
Both british thermal unit and ronnajoule measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in btu by 1.055055853e-24 to get ronnajoules. To reverse the conversion, multiply a ronnajoule value by 9.478171203e+23 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 Ronnajoule (RJ)?
A ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna prefix.
How do I convert btu to ronnajoules?
Multiply the british thermal unit value by 1.055055853e-24 to get the equivalent in ronnajoules. For example, 5 BTU × 1.055055853e-24 = 5.275279e-24 RJ.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 1.055055853e-24 is an exact, non-rounded value.
Can I convert ronnajoules back to btu?
Yes. Divide the ronnajoule value by 1.055055853e-24, or multiply it by 9.478171203e+23, to get btu.
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About converting btu to ronnajoules
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 ronnajoule (RJ) is a metric-prefixed unit of energy equal to 1027 joules, using the SI ronna prefix.
Use this calculator to move between btu and ronnajoules accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.