How to Convert Kilocalories to Therms (kcal to thm)
Energy conversions link food labels in kJ and kcal, SP Group bills in kWh and air-conditioner capacity in BTU. This guide shows how to convert kilocalories into therms by hand, with examples and a quick-reference table.
The conversion
To convert kilocalories to therms, multiply the value by 3.965667e-05. To go the other way, divide by the same number (or multiply by 25,216.4400709847). Because the factor is tiny, scientific notation keeps the numbers manageable.
Therms = kilocalories × 3.965667e-05
Worked examples
- 3 kcal = 0.000119 thm
- 12.5 kcal = 0.000496 thm
- 75 kcal = 0.002974 thm
Kilocalories to Therms table
| Kilocalories | Therms |
|---|---|
| 1 kcal | 3.965667e-5 thm |
| 2 kcal | 7.931334e-5 thm |
| 5 kcal | 0.000198 thm |
| 10 kcal | 0.000397 thm |
| 20 kcal | 0.000793 thm |
| 25 kcal | 0.000991 thm |
| 50 kcal | 0.001983 thm |
| 100 kcal | 0.003966 thm |
| 250 kcal | 0.009914 thm |
| 500 kcal | 0.019828 thm |
| 1,000 kcal | 0.039657 thm |
Common questions
Is kcal to thm exact?
The factors used here are the internationally defined values where they exist; results are rounded for display only.
How do I convert back?
Use the Therms to Kilocalories converter.
Mistakes to avoid
Rounding the factor too early
Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.
Forgetting squared and cubed units
Area and volume factors are the length factor squared or cubed, so 1 m² is about 10.76 sq ft, not 3.28.
Mixing similar-sounding units
US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.
Background
Writing the units next to every number while you work is the simplest way to avoid mistakes. If the units do not cancel to leave the one you want, the calculation is set up wrongly.
Many conversion factors are exact by definition. The inch has been defined as exactly 2.54 centimetres since 1959, and the pound as exactly 0.45359237 kilograms, so conversions involving them can be as precise as you need.
For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.
For any value, use the Kilocalories to Therms Converter or browse all energy converters.
Run your own numbers: Kilocalories to Therms Converter