Thermal conductivity converter
How well a material conducts heat (k-value). The degree in these units is a temperature difference, so 1 K and 1 °C are the same step, and 1 °F is 5/9 of it.
1 watt per metre kelvin = 0.57779 BTU per hour foot °F
How it’s calculated
BTU/(h·ft·°F) = W/(m·K) × 0.5777893165
- Multiply the value in watts per metre kelvin by 0.5777893165.
- To go back, divide by 0.5777893165 (or multiply by 1.730734666).
- 1 W/(m·K) = 0.5777893165 BTU/(h·ft·°F) · 1 BTU/(h·ft·°F) = 1.730734666 W/(m·K)
Show worked solutionFactor, unit cancellation and rounding, step by step
Find the conversion factor
By definition 1 BTU/(h·ft·°F) = 1.73073466637139 W/(m·K). Source: BIPM SI Brochure (9th ed.); NIST SP 811 / Handbook 44.
Multiply by the factor written as a fraction
Put W/(m·K) in the denominator so it cancels, leaving BTU/(h·ft·°F).
Calculate (unrounded)
Round the answer
Rounded to 5 significant figures.
Answer: 0.57779 BTU/(h·ft·°F)
1 W/(m·K) in other units
Batch convert W/(m·K) → BTU/(h·ft·°F)
- 1 W/(m·K) = 0.57779 BTU/(h·ft·°F)
- 5 W/(m·K) = 2.8889 BTU/(h·ft·°F)
- 10 W/(m·K) = 5.7779 BTU/(h·ft·°F)
- 25 W/(m·K) = 14.445 BTU/(h·ft·°F)
Common thermal conductivity conversions
Thermal conductivity units and exact definitions
| Unit | System | Definition |
|---|---|---|
| Watt per metre kelvin (W/(m·K)) | SI (metric) | Base unit |
| Watt per centimetre kelvin (W/(cm·K)) | SI (metric) | 1 W/(cm·K) = 100 W/(m·K) |
| BTU per hour foot °F (BTU/(h·ft·°F)) | US & imperial (identical) | 1 BTU/(h·ft·°F) = 1.730734666 W/(m·K) |
| BTU inch per hour square foot °F (BTU·in/(h·ft²·°F)) | US & imperial (identical) | 1 BTU·in/(h·ft²·°F) = 0.1442278889 W/(m·K) |
| Kilocalorie (IT) per hour metre °C (kcal_IT/(h·m·°C)) | other | 1 kcal_IT/(h·m·°C) = 1.163 W/(m·K) |
| Calorie (th) per second centimetre °C (cal_th/(s·cm·°C)) | other | 1 cal_th/(s·cm·°C) = 418.4 W/(m·K) |
Watts per metre kelvin to BTU per hour foot °F conversion table
| Watts per metre kelvin (W/(m·K)) | BTU per hour foot °F (BTU/(h·ft·°F)) |
|---|---|
| 0.025 W/(m·K) | 0.014445 BTU/(h·ft·°F) |
| 0.04 W/(m·K) | 0.023112 BTU/(h·ft·°F) |
| 0.1 W/(m·K) | 0.057779 BTU/(h·ft·°F) |
| 0.5 W/(m·K) | 0.28889 BTU/(h·ft·°F) |
| 1 W/(m·K) | 0.57779 BTU/(h·ft·°F) |
| 1.5 W/(m·K) | 0.86668 BTU/(h·ft·°F) |
| 15 W/(m·K) | 8.6668 BTU/(h·ft·°F) |
| 50 W/(m·K) | 28.889 BTU/(h·ft·°F) |
| 100 W/(m·K) | 57.779 BTU/(h·ft·°F) |
| 200 W/(m·K) | 115.56 BTU/(h·ft·°F) |
| 237 W/(m·K) | 136.94 BTU/(h·ft·°F) |
| 400 W/(m·K) | 231.12 BTU/(h·ft·°F) |
Frequently asked questions
Which thermal conductivity units can I convert?
watts per metre kelvin (W/(m·K)), watts per centimetre kelvin (W/(cm·K)), BTU per hour foot °F (BTU/(h·ft·°F)), BTU inch per hour square foot °F (BTU·in/(h·ft²·°F)), kilocalories (IT) per hour metre °C (kcal_IT/(h·m·°C)), calories (th) per second centimetre °C (cal_th/(s·cm·°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.