Convert Calorie to British Thermal Unit
Use this free converter to change calories (cal) into british thermal units (BTU). Calorie and british thermal unit both measure energy. As a quick reference, 1 cal equals 0.0039656668 BTU, and 1 BTU equals 252.1644 cal.
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British Thermal Unit (BTU)
0.0039656668
1 cal = 0.0039656668 BTU
Energy conversion table
| Calorie | British Thermal Unit |
|---|---|
| 0.01 | 0.000039656668 |
| 0.1 | 0.00039656668 |
| 0.5 | 0.0019828334 |
| 1 | 0.0039656668 |
| 2 | 0.0079313337 |
| 3 | 0.011897001 |
| 5 | 0.019828334 |
| 10 | 0.039656668 |
| 20 | 0.079313337 |
| 25 | 0.099141671 |
| 50 | 0.19828334 |
| 100 | 0.39656668 |
| 1,000 | 3.9656668 |
How to convert Calorie to British Thermal Unit
Multiply the calorie value by 0.0039656668 to get british thermal units.
- Enter the number of calories you want to convert.
- The converter instantly shows the equivalent value in british thermal units.
- Worked example: 15 cal × 0.0039656668 = 0.059485003 BTU.
- Use the swap button to reverse the conversion (british thermal unit to calorie).
About these units
Calorie (cal)
- Definition
- A calorie (cal) is the energy needed to raise one gram of water by one degree Celsius, about 4.184 joules.
- History
- Defined in the 19th century, the small calorie was later joined by the larger food Calorie.
- Current use
- Calories appear in chemistry and, as kilocalories, in nutrition.
British Thermal Unit (BTU)
- Definition
- A British thermal unit (BTU) is the energy needed to raise one pound of water by one degree Fahrenheit.
- History
- It developed with steam engineering in Britain and the United States.
- Current use
- BTUs rate heating, air-conditioning, and appliance energy in the US.
Frequently asked questions
How many british thermal units are in a calorie?
There are 0.0039656668 BTU in 1 cal. To convert, multiply the number of calories by 0.0039656668.
How do I convert calories to british thermal units?
Multiply the calorie value by 0.0039656668 to get british thermal units. For example, 10 cal = 0.039656668 BTU.
Is this calorie-to-british thermal unit converter free?
Yes. This converter is completely free, runs entirely in your browser, and requires no sign-up. Your inputs never leave your device.
Convert Calorie to other energy units
| Unit | 1 Calorie equals |
|---|---|
| Joule (J) | 4.184 J |
| Kilojoule (kJ) | 0.004184 kJ |
| Kilocalorie (kcal) | 0.001 kcal |
| Watt Hour (Wh) | 0.0011622222 Wh |
| Kilowatt Hour (kWh) | 0.0000011622222 kWh |
| Electronvolt (eV) | 2.6114e+19 eV |
| British Thermal Unit (BTU) | 0.0039656668 BTU |
| Foot-Pound (ft·lb) | 3.08596 ft·lb |