A femtojoule (fJ) is a metric-prefixed unit of energy equal to 10-15 joules, a fraction of a single joule, using the SI femto prefix.
Femtojoules to Therms
Convert Femtojoule (fJ) to US therm (therm) instantly with an exact formula, conversion table, and FAQ.
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Convert femtojoules (fJ) to therms (therm) instantly with formula, conversion table, and FAQ.
Context values
Some unit families need one extra value for a physically accurate result.
The US therm is a natural-gas billing unit equal to 100,000 BTU, used by utilities to measure gas usage.
therm = fJ × 9.480434280e-24
Results update instantly for Femtojoules to Therms conversions.
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Formula
therm = fJ × 9.480434280e-24
fJ = therm × 1.054804000e+23
Conversion table
| 1 fJ | 9.480434e-24 therm |
| 5 fJ | 4.740217e-23 therm |
| 10 fJ | 9.480434e-23 therm |
| 20 fJ | 1.896087e-22 therm |
| 50 fJ | 4.740217e-22 therm |
| 100 fJ | 9.480434e-22 therm |
| 500 fJ | 4.740217e-21 therm |
| 1000 fJ | 9.480434e-21 therm |
Related conversions
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How the formula works
Both femtojoule and us therm measure the same physical quantity, so converting between them is a single multiplication. Multiply a value in femtojoules by 9.480434280e-24 to get therms. To reverse the conversion, multiply a us therm value by 1.054804000e+23 to get back to femtojoules.
Frequently asked questions
What is Femtojoule (fJ)?
A femtojoule (fJ) is a metric-prefixed unit of energy equal to 10-15 joules, a fraction of a single joule, using the SI femto prefix.
What is US therm (therm)?
The US therm is a natural-gas billing unit equal to 100,000 BTU, used by utilities to measure gas usage.
How do I convert femtojoules to therms?
Multiply the femtojoule value by 9.480434280e-24 to get the equivalent in therms. For example, 5 fJ × 9.480434280e-24 = 4.740217e-23 therm.
Is this conversion exact?
Yes. Both units are defined against the SI base unit for this dimension, so the factor 9.480434280e-24 is an exact, non-rounded value.
Can I convert therms back to femtojoules?
Yes. Divide the us therm value by 9.480434280e-24, or multiply it by 1.054804000e+23, to get femtojoules.
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About converting femtojoules to therms
A femtojoule (fJ) is a metric-prefixed unit of energy equal to 10-15 joules, a fraction of a single joule, using the SI femto prefix. The US therm is a natural-gas billing unit equal to 100,000 BTU, used by utilities to measure gas usage.
Use this calculator to move between femtojoules and therms accurately for homework, engineering, billing, or everyday energy calculations. The Universal Converter uses exact unit factors, so results stay consistent across the site.