Convert energy units — joules, kilowatt-hours, calories, BTU, electron volts and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 therm | 99.9757 BTU | |
| 0.01 therm | 999.757 BTU | |
| 0.1 therm | 9997.57 BTU | |
| 1 therm | 99975.7 BTU | |
| 5 therm | 499879 BTU | |
| 10 therm | 999757 BTU | |
| 50 therm | 4.99879e+06 BTU | |
| 100 therm | 9.99757e+06 BTU | |
| 1000 therm | 9.99757e+07 BTU |
Formula: BTU = Therm × 99,980
Multiply any therm value by 99,980 to get btu.
Reverse: Therm = BTU × 1.0002e-5
Common therm values — factor: 1 therm = 99,980 BTU
| Therm (therm) | BTU (BTU) | Context |
|---|---|---|
| 0.001 therm | 99.98 BTU | 0.1 kWh |
| 0.01 therm | 999.8 BTU | 1 kWh |
| 0.1 therm | 9,998 BTU | 3 kWh |
| 1 therm | 9.998e+04 BTU | 29.3 kWh |
| 10 therm | 9.998e+05 BTU | Monthly gas fraction |
| 50 therm | 4.999e+06 BTU | Half winter month |
| 100 therm | 9.998e+06 BTU | Monthly winter gas |
| 500 therm | 4.999e+07 BTU | Seasonal heating |
| 1,000 therm | 9.998e+07 BTU | Annual home gas |
| 1e+04 therm | 9.998e+08 BTU | Commercial building |
| 1e+05 therm | 9.998e+09 BTU | Large industrial |
| 1e+06 therm | 9.998e+10 BTU | Utility scale |
| 1.000e+09 therm | 9.998e+13 BTU | Regional supply |
| 1.000e+12 therm | 9.998e+16 BTU | National supply |
| 1.000e+15 therm | 9.998e+19 BTU | Global scale |
1 therm = 99,980 BTU. Memorize for instant estimates.
Use 99,980 as a quick mental multiplier.
Multiply result by 1.0002e-5 to recover the original therm value.
Bills residential and commercial customers in therms per billing cycle.
Calculates annual gas consumption for boilers and furnaces in therms.
Trades natural gas contracts denominated in therms or MMBTU.
Monitors and benchmarks gas use in therms per square foot per year.
Sizes gas pipes and appliances based on BTU/hour and therm ratings.
Models household and industrial gas demand in therms per year.
The therm is a unit of natural gas energy equal to 100,000 BTU (105,480,400 joules). It is the standard billing unit for natural gas in the United States and United Kingdom. The name comes from the Greek thermos (heat).
Gas utilities bill residential and commercial customers in therms in the US and UK. A typical US household uses about 50–100 therms per month in winter. Natural gas furnaces and water heaters are rated in therms per hour.
Interesting fact: One therm of natural gas costs about $1.00–$2.00 in the US. Burning one therm releases about 5.3 kg of CO₂. The US consumes about 28 trillion therms of natural gas equivalent energy per year.
The British Thermal Unit (BTU) is the traditional Imperial energy unit, defined as the heat required to raise 1 pound of water by 1°F. It equals 1,055.06 joules and has been used since the 19th century in heating, air conditioning, and gas billing.
BTU remains dominant in US HVAC: air conditioners and heaters are rated in BTU/hour. Natural gas is priced in therms (100,000 BTU) in the US. Furnaces are rated in BTU/hour output.
Interesting fact: A typical US home furnace is rated at 80,000–120,000 BTU/hour. One BTU is roughly the energy released by burning one kitchen match. The US natural gas pipeline system delivers about 25 quadrillion BTU (quads) per year.
Converting therm to btu is common across energy, nutrition, engineering, and science. Different sectors use different energy units — joules in physics, kcal in nutrition, kWh in electricity, and BTU in HVAC — making accurate conversion essential for cross-disciplinary work and international comparisons.
Quick reference: 5 therm = 499,900 BTU and 10 therm = 999,800 BTU. Reverse: 1 BTU = 1.0002e-5 therm. Exact factor: 1 therm = 99,980 BTU.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.