Therms (thm)
The therm is 100,000 BTU, about 105.5 MJ or 29.3 kWh.
Convert therms to any energy unit
1 therm = 105,480,400 joules
Quick facts
- Unit
- Therm (plural: therms)
- Symbol
- thm
- Measures
- Energy / Work / Heat
- System
- BTU & therms
- Equals
- 105,480,400 joules
- Definition
- 100,000 BTU₅₉ (105,480,400 J), the US therm.
- Also written
- US therm
1 therm in other units
| Joules | 105,480,400 J |
| Kilocalories | 25,210.42065 kcal |
| Kilowatt-hours | 29.30011111 kWh |
| British thermal units | 99,976.12898 BTU |
| Calories | 25,210,420.65 cal |
| Kilojoules | 105,480.4 kJ |
| Calories (food) | 25,210.42065 Cal |
| Electronvolts | 6.5835687 × 1026 eV |
What is a therm?
The therm is 100,000 BTU, about 105.5 MJ or 29.3 kWh. US and UK natural gas bills are measured in therms. The US therm is based on the 59 °F BTU; the EU therm is slightly larger.
Where the therm sits among energy units
The therm is number 63 of 99 on our scale of energy units, ordered from smallest to largest.
Therms in real life
- A typical US home uses 500–1,000 therms of gas a year
- 1 therm ≈ 29.3 kWh ≈ 97 ft³ of natural gas
One therm is about the energy of 3.1 liters of gasoline, or about the energy of 13 days of an adult's food, or about the energy of 45 Big Macs, or about the energy of 240 bananas.
Top therm conversions
Common amounts of therms
- 0.25 thm
- 0.5 thm
- 0.75 thm
- 1 thm
- 1.5 thm
- 2 thm
- 2.5 thm
- 3 thm
- 4 thm
- 5 thm
- 6 thm
- 7 thm
- 8 thm
- 9 thm
- 10 thm
- 11 thm
- 12 thm
- 13 thm
- 14 thm
- 15 thm
- 16 thm
- 17 thm
- 18 thm
- 19 thm
- 20 thm
- 21 thm
- 22 thm
- 23 thm
- 24 thm
- 25 thm
- 26 thm
- 27 thm
- 28 thm
- 29 thm
- 30 thm
- 31 thm
- 32 thm
- 33 thm
- 34 thm
- 35 thm
- 36 thm
- 37 thm
- 38 thm
- 39 thm
- 40 thm
- 41 thm
- 42 thm
- 43 thm
- 44 thm
- 45 thm
- 46 thm
- 47 thm
- 48 thm
- 49 thm
- 50 thm
- 60 thm
- 70 thm
- 80 thm
- 90 thm
- 100 thm
- 150 thm
- 200 thm
- 250 thm
- 300 thm
- 400 thm
- 500 thm
- 750 thm
- 1,000 thm
Convert therms to all 98 other units
Metric (SI)
Electrical
Calories
- thm to kcal
- thm to cal
- thm to Cal
- thm to cal_IT
- thm to Gcal
- thm to Mcal
- thm to cal₁₅
- thm to th
- thm to cal₂₀
- thm to cal_mean
BTU & therms
- thm to BTU
- thm to MMBtu
- thm to MBtu
- thm to Dth
- thm to quad
- thm to thm (EC)
- thm to BTU_th
- thm to BTU₅₉
- thm to CHU
- thm to Q
- thm to BTU₃₉
- thm to BTU₆₀
- thm to BTU_mean
Mechanical
- thm to ft⋅lbf
- thm to erg
- thm to in⋅lbf
- thm to hp⋅h
- thm to L⋅atm
- thm to kgf⋅m
- thm to ft⋅pdl
- thm to in⋅ozf
- thm to PS⋅h
- thm to cm³⋅atm
- thm to ft³⋅atm
- thm to ft³⋅psi
Atomic & physics
- thm to eV
- thm to MeV
- thm to GeV
- thm to keV
- thm to TeV
- thm to Eh
- thm to kJ/mol
- thm to kcal/mol
- thm to meV
- thm to cm⁻¹
- thm to EP
- thm to PeV
- thm to Ry
- thm to EeV
- thm to K·k_B
- thm to foe
- thm to h·Hz
Fuel & explosive equivalents
- thm to BOE
- thm to t TNT
- thm to toe
- thm to kt
- thm to Mt
- thm to cubic foot of natural gas
- thm to GGE
- thm to Mtoe
- thm to cubic meter of natural gas
- thm to tce
- thm to ktoe
- thm to liter of gasoline
- thm to Gt
- thm to g TNT
- thm to kg TNT
- thm to MMBOE
- thm to kBOE
- thm to DGE
Everyday comparisons
Convert to therms
Frequently asked questions
What is a therm?
The therm is 100,000 BTU, about 105.5 MJ or 29.3 kWh.
How is the therm defined?
100,000 BTU₅₉ (105,480,400 J), the US therm.
How many joules are in a therm?
One therm equals 105,480,400 joules.
How many kilocalories are in a therm?
One therm equals 25,210.42065 kilocalories.
How many kilowatt-hours are in a therm?
One therm equals 29.30011111 kilowatt-hours.