Heat transfer coefficient converter
Convective heat transfer coefficients (h) and building U-values. Temperatures here are differences (intervals), not absolute readings.
1 watt per square metre kelvin = 0.17611 BTU per hour square foot °F
How it’s calculated
BTU/(h·ft²·°F) = W/(m²·K) × 0.1761101837
- Multiply the value in watts per square metre kelvin by 0.1761101837.
- To go back, divide by 0.1761101837 (or multiply by 5.678263341).
- 1 W/(m²·K) = 0.1761101837 BTU/(h·ft²·°F) · 1 BTU/(h·ft²·°F) = 5.678263341 W/(m²·K)
Show worked solutionFactor, unit cancellation and rounding, step by step
Find the conversion factor
By definition 1 BTU/(h·ft²·°F) = 5.67826334111349 W/(m²·K). Source: BIPM SI Brochure (9th ed.); NIST SP 811 / Handbook 44.
Multiply by the factor written as a fraction
Put W/(m²·K) in the denominator so it cancels, leaving BTU/(h·ft²·°F).
Calculate (unrounded)
Round the answer
Rounded to 5 significant figures.
Answer: 0.17611 BTU/(h·ft²·°F)
1 W/(m²·K) in other units
Batch convert W/(m²·K) → BTU/(h·ft²·°F)
- 1 W/(m²·K) = 0.17611 BTU/(h·ft²·°F)
- 5 W/(m²·K) = 0.88055 BTU/(h·ft²·°F)
- 10 W/(m²·K) = 1.7611 BTU/(h·ft²·°F)
- 25 W/(m²·K) = 4.4028 BTU/(h·ft²·°F)
Common heat transfer coefficient conversions
Heat transfer coefficient units and exact definitions
| Unit | System | Definition |
|---|---|---|
| Watt per square metre kelvin (W/(m²·K)) | SI (metric) | Base unit |
| Kilowatt per square metre kelvin (kW/(m²·K)) | SI (metric) | 1 kW/(m²·K) = 1000 W/(m²·K) |
| Watt per square centimetre kelvin (W/(cm²·K)) | SI (metric) | 1 W/(cm²·K) = 10000 W/(m²·K) |
| BTU per hour square foot °F (BTU/(h·ft²·°F)) | US & imperial (identical) | 1 BTU/(h·ft²·°F) = 5.678263341 W/(m²·K) |
| Kilocalorie (IT) per hour square metre °C (kcal_IT/(h·m²·°C)) | other | 1 kcal_IT/(h·m²·°C) = 1.163 W/(m²·K) |
Watts per square metre kelvin to BTU per hour square foot °F conversion table
| Watts per square metre kelvin (W/(m²·K)) | BTU per hour square foot °F (BTU/(h·ft²·°F)) |
|---|---|
| 0.1 W/(m²·K) | 0.017611 BTU/(h·ft²·°F) |
| 0.15 W/(m²·K) | 0.026417 BTU/(h·ft²·°F) |
| 0.2 W/(m²·K) | 0.035222 BTU/(h·ft²·°F) |
| 0.25 W/(m²·K) | 0.044028 BTU/(h·ft²·°F) |
| 0.3 W/(m²·K) | 0.052833 BTU/(h·ft²·°F) |
| 0.5 W/(m²·K) | 0.088055 BTU/(h·ft²·°F) |
| 1 W/(m²·K) | 0.17611 BTU/(h·ft²·°F) |
| 1.5 W/(m²·K) | 0.26417 BTU/(h·ft²·°F) |
| 2 W/(m²·K) | 0.35222 BTU/(h·ft²·°F) |
| 5 W/(m²·K) | 0.88055 BTU/(h·ft²·°F) |
| 10 W/(m²·K) | 1.7611 BTU/(h·ft²·°F) |
| 25 W/(m²·K) | 4.4028 BTU/(h·ft²·°F) |
| 50 W/(m²·K) | 8.8055 BTU/(h·ft²·°F) |
| 100 W/(m²·K) | 17.611 BTU/(h·ft²·°F) |
| 1,000 W/(m²·K) | 176.11 BTU/(h·ft²·°F) |
Frequently asked questions
Which heat transfer coefficient units can I convert?
watts per square metre kelvin (W/(m²·K)), kilowatts per square metre kelvin (kW/(m²·K)), watts per square centimetre kelvin (W/(cm²·K)), BTU per hour square foot °F (BTU/(h·ft²·°F)), kilocalories (IT) per hour square metre °C (kcal_IT/(h·m²·°C)).
How accurate are the results?
Every unit is stored with its exact defining factor (NIST SP 811, NIST Handbook 44 or the BIPM SI Brochure). Calculations use double-precision arithmetic and are rounded only for display, to 5 significant figures by default (trailing zeros dropped, so 1 km shows as 1000 m). You can choose Auto (up to 10 digits), fixed decimals or more significant figures, or switch to scientific or engineering notation.
Why do °C, K and °F appear without an offset here?
In these units the temperature is a temperature difference (an interval), not a reading. A difference of 1 K equals 1 °C and 1 °F equals 5/9 K, so only the scale factor applies and the 32° or 273.15° offset never does.