Convert energy units — joules, kilowatt-hours, calories, BTU, electron volts and more.
| Unit | Name | Value |
|---|---|---|
| 0.001 cal | 3.967e-11 therm | |
| 0.01 cal | 3.967e-10 therm | |
| 0.1 cal | 3.96661e-09 therm | |
| 1 cal | 3.96661e-08 therm | |
| 5 cal | 1.98331e-07 therm | |
| 10 cal | 3.96661e-07 therm | |
| 50 cal | 1.98331e-06 therm | |
| 100 cal | 3.96661e-06 therm | |
| 1000 cal | 3.96661e-05 therm |
Formula: Therm = Calorie × 3.9666e-8
Multiply any calorie value by 3.9666e-8 to get therm.
Reverse: Calorie = Therm × 2.521e+07
Common calorie values — factor: 1 cal = 3.9666e-8 therm
| Calorie (cal) | Therm (therm) | Context |
|---|---|---|
| 1 cal | 3.967e-08 therm | 1 cal |
| 5 cal | 1.983e-07 therm | 5 cal |
| 10 cal | 3.967e-07 therm | Small candy |
| 50 cal | 1.983e-06 therm | 50 cal |
| 100 cal | 3.967e-06 therm | Short walk |
| 500 cal | 1.983e-05 therm | Snack |
| 1,000 cal | 3.967e-05 therm | Light meal |
| 5,000 cal | 0.0001983 therm | Meal |
| 1e+04 cal | 0.0003967 therm | Large meal |
| 5e+04 cal | 0.001983 therm | Daily intake fraction |
| 1e+05 cal | 0.003967 therm | 100 kcal |
| 5e+05 cal | 0.01983 therm | 500 kcal workout |
| 1e+06 cal | 0.03967 therm | 1 Mcal |
| 1.000e+09 cal | 39.67 therm | 1 Gcal |
| 1.000e+12 cal | 3.967e+04 therm | 1 Tcal |
1 cal = 3.9666e-8 therm. Memorize for instant estimates.
Use 3.9666e-8 as a quick mental multiplier.
Multiply result by 2.521e+07 to recover the original cal 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 calorie (cal) was defined in 1824 as the heat needed to raise 1 gram of water by 1°C. There are two versions: the small calorie (cal = 4.184 J) and the large calorie or kilocalorie (kcal = 4,184 J), which is the 'Calorie' used in nutrition.
The calorie remains standard in chemistry for heat of reaction measurements. In the US, food packaging uses 'Calories' (with capital C) which are actually kilocalories — a persistent source of confusion.
Interesting fact: The confusion between cal and kcal means that a food label saying '200 Calories' actually means 200 kcal = 200,000 cal = 836,800 joules. The SI unit for food energy is the kilojoule.
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.
Converting calorie to therm 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 cal = 1.9833e-7 therm and 10 cal = 3.9666e-7 therm. Reverse: 1 therm = 2.521e+07 cal. Exact factor: 1 cal = 3.9666e-8 therm.
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.