How to convert British thermal units to kilocalories
kcal = BTU × 0.2521644007Multiply the value in British thermal units by 0.2521644007. To go the other way, multiply by 3.965666831 (or divide by 0.2521644007).
A British thermal unit is smaller than a kilocalorie: it takes 3.965666831 British thermal units to make one kilocalorie.
Worked examples
- 1 British thermal unit1 BTU × 0.2521644007 = 0.2521644007 kcal
- 5 British thermal units5 BTU × 0.2521644007 = 1.260822004 kcal
- 10 British thermal units10 BTU × 0.2521644007 = 2.521644007 kcal
- 20 British thermal units20 BTU × 0.2521644007 = 5.043288014 kcal
- 100 British thermal units100 BTU × 0.2521644007 = 25.21644007 kcal
British thermal units to kilocalories conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| British thermal units (BTU) | Kilocalories (kcal) |
|---|---|
| 0.1 BTU | 0.02521644 kcal |
| 0.25 BTU | 0.0630411 kcal |
| 0.5 BTU | 0.1260822 kcal |
| 1 BTU | 0.2521644 kcal |
| 2 BTU | 0.5043288 kcal |
| 3 BTU | 0.7564932 kcal |
| 4 BTU | 1.0086576 kcal |
| 5 BTU | 1.260822 kcal |
| 6 BTU | 1.5129864 kcal |
| 7 BTU | 1.7651508 kcal |
| 8 BTU | 2.0173152 kcal |
| 9 BTU | 2.2694796 kcal |
| 10 BTU | 2.521644 kcal |
| British thermal units (BTU) | Kilocalories (kcal) |
|---|---|
| 12 BTU | 3.0259728 kcal |
| 15 BTU | 3.782466 kcal |
| 20 BTU | 5.043288 kcal |
| 25 BTU | 6.30411 kcal |
| 30 BTU | 7.564932 kcal |
| 40 BTU | 10.086576 kcal |
| 50 BTU | 12.60822 kcal |
| 75 BTU | 18.91233 kcal |
| 100 BTU | 25.21644 kcal |
| 250 BTU | 63.0411 kcal |
| 500 BTU | 126.0822 kcal |
| 1,000 BTU | 252.1644 kcal |
About the units
British thermal unit (BTU)
The International Table BTU, 1,055.05585262 J — roughly the energy to heat one pound of water by 1 °F. Furnace and AC capacities are rated in BTU (per hour). One British thermal unit equals 1,055.055853 joules (J).
Kilocalorie (kcal)
One thousand small calories, or 4,184 J. The “Calories” on nutrition labels are kilocalories.
Frequently asked questions
How many kilocalories are in one British thermal unit?
There are 0.2521644007 kilocalories in one British thermal unit, and this value is exact by definition.
How do I convert British thermal units to kilocalories?
Multiply the number of British thermal units by 0.2521644007. For example, 10 BTU × 0.2521644007 = 2.521644007 kcal.
How many British thermal units are in one kilocalorie?
One kilocalorie equals 3.965666831 British thermal units. That is the reverse factor, 1 ÷ 0.2521644007.
What is 10 British thermal units in kilocalories?
10 BTU = 2.521644007 kcal.
Is this BTU to kcal converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.