Convert Btu (IT) per Hour per Square Foot per °F to Kilocalories (IT) per Hour per Square Foot per °C
Btu (IT) per Hour per Square Foot per °F (Btu/(h·ft²·°F)) to Kilocalorie (IT) per Hour per Square Foot per °C (kcal/(h·ft²·°C)) heat transfer coefficient conversion — enter any value below to get an instant result, or use the table for common values.
Results from this calculator are estimates provided for general informational purposes only, based on formulas, rates, and standards commonly accepted as of 2026. Figures may differ slightly from other calculators or professional sources due to rounding methods, differing assumptions, or regional regulations, and rules may change over time. Always consult a qualified professional — such as a financial advisor, healthcare provider, or other relevant specialist — before making decisions based on these results.
Result
1 Btu/(h·ft²·°F) = 0.45359237 kcal/(h·ft²·°C)
1 Btu (IT) per Hour per Square Foot per °F = 0.45359237 Kilocalories (IT) per Hour per Square Foot per °C
1 Kilocalorie (IT) per Hour per Square Foot per °C = 2.2046226 Btu (IT) per Hour per Square Foot per °F
1 Btu/(h·ft²·°F) in every supported unit
Conversion chart: Btu (IT) per Hour per Square Foot per °F to Kilocalories (IT) per Hour per Square Foot per °C
Conversion table
| Btu (IT) per Hour per Square Foot per °F (Btu/(h·ft²·°F)) | Kilocalorie (IT) per Hour per Square Foot per °C (kcal/(h·ft²·°C)) |
|---|---|
| 0.01 Btu/(h·ft²·°F) | 0.0045359237 kcal/(h·ft²·°C) |
| 0.1 Btu/(h·ft²·°F) | 0.045359237 kcal/(h·ft²·°C) |
| 1 Btu/(h·ft²·°F) | 0.45359237 kcal/(h·ft²·°C) |
| 2 Btu/(h·ft²·°F) | 0.90718474 kcal/(h·ft²·°C) |
| 3 Btu/(h·ft²·°F) | 1.3607771 kcal/(h·ft²·°C) |
| 5 Btu/(h·ft²·°F) | 2.2679618 kcal/(h·ft²·°C) |
| 10 Btu/(h·ft²·°F) | 4.5359237 kcal/(h·ft²·°C) |
| 20 Btu/(h·ft²·°F) | 9.0718474 kcal/(h·ft²·°C) |
| 50 Btu/(h·ft²·°F) | 22.679618 kcal/(h·ft²·°C) |
| 100 Btu/(h·ft²·°F) | 45.359237 kcal/(h·ft²·°C) |
| 1000 Btu/(h·ft²·°F) | 453.59237 kcal/(h·ft²·°C) |
Btu (IT) per Hour per Square Foot per °F (Btu/(h·ft²·°F))
Definition: The standard US customary heat transfer coefficient — British thermal units crossing one square foot of surface per hour, per degree Fahrenheit of temperature difference.
History: Built from the Btu, hour, square foot, and Fahrenheit degree, all standard US HVAC measurements, giving American engineers a film-coefficient figure matching everyday design calculations.
Current use: The standard "h" (film coefficient) unit throughout US HVAC and heat-exchanger design, forming a key input to convective heat-transfer calculations in ASHRAE design guides.
Kilocalorie (IT) per Hour per Square Foot per °C (kcal/(h·ft²·°C))
Definition: A mixed-unit heat transfer coefficient combining the metric kilocalorie and Celsius degree with the US customary square foot, reflecting internationally blended engineering documentation.
History: Emerged in international heat-exchanger equipment documentation that mixes metric energy and temperature units with US customary area units.
Current use: Occasionally seen in internationally traded HVAC and heat-exchanger equipment specifications that blend metric and US customary conventions.
Supported Units
| Unit | Symbol | In W/(m²·K) |
|---|---|---|
| Watt per Square Meter per Kelvin | W/(m²·K) | 1 W/(m²·K) |
| Kilocalorie (IT) per Hour per Square Meter per °C | kcal/(h·m²·°C) | 1.163 W/(m²·K) |
| Calorie (IT) per Second per Square Centimeter per °C | cal/(s·cm²·°C) | 41868 W/(m²·K) |
| Btu (IT) per Hour per Square Foot per °F | Btu/(h·ft²·°F) | 5.6782633 W/(m²·K) |
| Btu (th) per Hour per Square Foot per °F | Btu(th)/(h·ft²·°F) | 5.6744659 W/(m²·K) |
| Btu (IT) per Second per Square Foot per °F | Btu/(s·ft²·°F) | 20441.748 W/(m²·K) |
| Kilocalorie (IT) per Hour per Square Foot per °C | kcal/(h·ft²·°C) | 12.518428 W/(m²·K) |
About These Parameters
- Value
- The heat transfer coefficient value you want to convert, expressed in the "From" unit. Accepts decimals.
- From Unit
- The unit your input value is currently measured in — a physics reference's W/(m²·K), or a US HVAC design guide's Btu/(h·ft²·°F).
- To Unit
- The unit you want the result converted into. Use the swap button to flip From and To instantly.
How Heat Transfer Coefficient Conversion Works
The Formula
Every unit here is defined by a fixed multiplier relative to watts per square meter per kelvin. To convert a value from one unit to another:
result = value × (factor of "From" unit ÷ factor of "To" unit)
For Btu (IT) per Hour per Square Foot per °F → Kilocalorie (IT) per Hour per Square Foot per °C: multiply by 0.45359237. For example, 1 Btu/(h·ft²·°F) × 0.45359237 = 0.45359237 kcal/(h·ft²·°C).
Newton's Law of Cooling
The heat transfer coefficient (h) is the proportionality constant in Newton's law of cooling: heat flux = h × (surface temperature − fluid temperature). A larger h means heat moves faster for the same temperature difference — still air might have h around 5-25 W/(m²·K), while forced water flow can reach several thousand, which is exactly why liquid cooling systems outperform air cooling by such a wide margin in high-power electronics and industrial equipment.
Convection vs. Conduction
This converter's units describe convective heat transfer — heat carried by a moving fluid touching a surface. That's a different physical mechanism from conduction, covered by the site's Thermal Conductivity Converter, which describes heat moving THROUGH a solid material. A complete heat-transfer calculation (like sizing a heat exchanger or predicting a building's heat loss) typically needs both: conduction through the walls or tube material, and convection at each fluid-contacted surface.
Example
A heat transfer coefficient of 1 Btu/(h·ft²·°F) equals 0.45359237 kcal/(h·ft²·°C). For scale, natural (unforced) air convection typically gives coefficients around 5-25 W/(m²·K), forced air convection (a fan) around 10-200 W/(m²·K), and forced water convection can reach 500-10,000 W/(m²·K) or higher.
Frequently Asked Questions
How many Kilocalories (IT) per Hour per Square Foot per °C are in 1 Btu (IT) per Hour per Square Foot per °F?
1 Btu (IT) per Hour per Square Foot per °F (Btu/(h·ft²·°F)) equals exactly 0.45359237 Kilocalories (IT) per Hour per Square Foot per °C (kcal/(h·ft²·°C)).
What's the difference between this and the Thermal Resistance Converter?
Heat transfer coefficient (this page) is a per-area rate — watts per square meter per degree. Thermal Resistance (a separate converter on this site) is a single-point figure without an area term — kelvin per watt — more suited to whole components like an electronics package. They're related but describe convection at a surface versus overall resistance of an object.
Why is water so much better than air at heat transfer?
Water has both a much higher density and specific heat capacity than air, and moving water carries far more thermal energy per unit volume than moving air for the same temperature rise — which translates directly into a much higher convective heat transfer coefficient, often 20-100 times greater for comparable flow conditions.
How accurate are these conversions?
Every conversion factor used here is the exact, internationally recognized relationship between the underlying power, area, and temperature units — results are limited only by floating-point display precision, not by rounded conversion constants.