Kilocalories to British Thermal Units Converter
One Kilocalorie equals 3.965666831 British Thermal Units (1 kcal = 3.965666831 BTU). Multiply a Kilocalorie value by 3.965666831 to get the equivalent in British Thermal Units. Enter a value above to calculate the result. You can also use the formula and reference table below.
Formula
BTU = kcal × 3.965666831
Multiply the Kilocalorie value by 3.965666831 to get the equivalent value in British Thermal Units.
Example Conversions
1 Kilocalorie (kcal)
3.965666831 British Thermal Unit (BTU)
5 Kilocalorie (kcal)
19.82833416 British Thermal Unit (BTU)
10 Kilocalorie (kcal)
39.65666831 British Thermal Unit (BTU)
25 Kilocalorie (kcal)
99.14167078 British Thermal Unit (BTU)
100 Kilocalorie (kcal)
396.5666831 British Thermal Unit (BTU)
Conversion Table
| Kilocalorie (kcal) | British Thermal Unit (BTU) |
|---|---|
| 0.1 | 0.3965666831 |
| 0.5 | 1.982833416 |
| 1 | 3.965666831 |
| 2 | 7.931333663 |
| 5 | 19.82833416 |
| 10 | 39.65666831 |
| 25 | 99.14167078 |
| 50 | 198.2833416 |
| 100 | 396.5666831 |
| 250 | 991.4167078 |
| 500 | 1982.833416 |
| 1000 | 3965.666831 |
How to Convert Manually
Use these steps to convert Kilocalorie values to British Thermal Unit without the calculator.
- Write down the value in Kilocalorie (kcal) that you want to convert.
- Multiply that value by 3.965666831.
- For example, 10 Kilocalories × 3.965666831 = 39.65666831 British Thermal Units.
- Label the result as British Thermal Unit (BTU).
Relative Size Comparison
This chart shows the visual difference in size between exactly one Kilocalorie and one British Thermal Unit.
About Kilocalorie and British Thermal Unit
The kilocalorie is 4,184 joules. It is the food 'Calorie' (capital C) on US nutrition labels. Diet tracking and exercise burn estimates use kilocalories. The British thermal unit is about 1,055.06 joules, the heat to raise one pound of water by 1 °F. US heating and cooling equipment is rated in BTU per hour. One Kilocalorie equals 3.965666831 British Thermal Units (1 kcal = 3.965666831 BTU). Kilocalorie is used in nutrition labels and diet tracking and in exercise calorie burn. British Thermal Unit is used in air conditioner and furnace ratings in the US.
Precision and Rounding:Energy factors mix exact definitions (1 kWh = 3,600,000 J; 1 cal = 4.184 J thermochemical) with measured conventions (1 BTU ≈ 1,055.056 J). Nutrition and utility bills round to whole units; engineering heat calculations should keep the full factor until the final step.
Conversion factors per NIST Special Publication 811 and the BIPM SI Brochure (9th edition) (reference).
Worked Example
15Kilocalories equals59.48500247British Thermal Units.
15 kcal × 3.965666831 = 59.48500247 BTU
FAQ
How do I convert Kilocalorie to British Thermal Unit?
Multiply the Kilocalorie value by 3.965666831 to get the equivalent value in British Thermal Units.
What is the formula for Kilocalorie to British Thermal Unit?
The formula is BTU = kcal × 3.965666831.
How many British Thermal Units are in 1 Kilocalorie?
1 Kilocalorie equals 3.965666831 British Thermal Units.
Can I convert British Thermal Unit back to Kilocalorie?
Yes. 1 British Thermal Unit equals 0.2521644007 Kilocalories, and the related converter can reverse the calculation.
What are common names for Kilocalorie and British Thermal Unit?
Kilocalorie is shown as kcal and may also be searched as kilocalorie, kilocalories, food calorie. British Thermal Unit is shown as BTU and may also be searched as btu, british thermal unit.
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