Convert Therms to Joules
1 therm (thm) equals 105480400 joules (J).
1 thm = 105480400 J
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk therm to joule converter to paste a column from Excel.
How to Convert Therm to Joule
- 1 thm = 105480400 J
- 1 J = 9.48043428 × 10⁻⁹ thm
- Example: convert 15 thm to J: 15 thm = 15 × 105480400 J = 1582206000 J
Reference conditions. thm: US therm, 100 000 BTU (59 °F), 105.4804 MJ as given by NIST SP 811. The EC therm is 105.506 MJ.
Formula
J = thm × 105480400
Derivation from SI units:
- 1 thm (US) = 1.054804 × 10⁸ J (NIST SP 811)
- 1 J = 1 N·m = 1 W·s = 1 kg·m²·s⁻²
Both units are defined exactly, so the factor is exact. Therm definition: therm; Joule definition: joule.
Worked examples
- A reading of 20 thm converts to 2109608000 J.
20 thm × 105480400 = 2109608000 J - A value of 100 thm is 10548040000 J.
100 thm × 105480400 = 10548040000 J
Therm to Joule conversion table
| Therms (thm) | Joules (J) |
|---|---|
| 1 thm | 105480400 J |
| 5 thm | 527402000 J |
| 10 thm | 1054804000 J |
| 20 thm | 2109608000 J |
| 50 thm | 5274020000 J |
| 75 thm | 7911030000 J |
| 100 thm | 10548040000 J |
| 500 thm | 52740200000 J |
| 1000 thm | 105480400000 J |
Where it's used
Therms are used for US and UK natural-gas bills, while joules appear in physics and engineering energy balances. Both measure energy, work and heat, so the conversion is a fixed factor.
Therm to other energy units
| Conversion | 1 thm equals |
|---|---|
| therm to joule | 105480400 J |
| therm to kilojoule | 105480.4 kJ |
| therm to megajoule | 105.4804 MJ |
| therm to calorie | 25210420.65 cal |
| therm to kilocalorie | 25210.42065 kcal |
| therm to watt-hour | 29300.11111 Wh |
| therm to kilowatt-hour | 29.30011111 kWh |
| therm to BTU | 99976.12898 BTU |
| therm to electronvolt | 6.583568738 × 10²⁶ eV |
| therm to foot-pound | 77798350.53 ft·lbf |
| therm to erg | 1.054804 × 10¹⁵ erg |
Frequently asked questions
How many joules are in 1 therm?
1 thm = 105480400 J.
How do I convert therms to joules?
Multiply the value in thm by 105480400. For example, 15 thm × 105480400 = 1582206000 J.
Is the thm to J conversion exact?
Yes. Both units are defined exactly, and 1 thm is exactly 105480400 J.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "therm (U.S.)".
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 4, coherent derived units with special names.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Therms to Joules. Retrieved October 17, 2026, from https://scientificconverters.com/energy/therms-to-joules/
IEEE
Scientific Converters, "Convert Therms to Joules," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/energy/therms-to-joules/