Convert thermal conductivity units — W/(m·K), BTU/(h·ft·°F), cal/(s·cm·°C) and more.
| Unit | Name | Value |
|---|---|---|
| W/(m·K) | Watt/(Meter·Kelvin) | 418.68 |
| kW/(m·K) | Kilowatt/(Meter·Kelvin) | 0.41868 |
| BTU/(h·ft·°F) | BTU/(Hour·Foot·°F) | 241.90948 |
| kcal/(h·m·°C) | Kilocalorie/(Hour·m·°C) | 360 |
Formula: kcal/(h·m·°C) = cal/(s·cm·K) × 360
Multiply any cal/(s·cm·K) value by 360 to get kcal/(h·m·°C).
Reverse: cal/(s·cm·K) = kcal/(h·m·°C) × 0.002778
Copper reference: 0.9578 cal/(s·cm·K) = 344.8 kcal/(h·m·°C)
Factor: 1 cal/(s·cm·K) = 360 kcal/(h·m·°C)
| cal/(s·cm·K) (cal/(s·cm·K)) | kcal/(h·m·°C) (kcal/(h·m·°C)) | Material |
|---|---|---|
| 5.255 cal/(s·cm·K) | 1892 kcal/(h·m·°C) | Diamond |
| 1.025 cal/(s·cm·K) | 368.9 kcal/(h·m·°C) | Silver |
| 0.9578 cal/(s·cm·K) | 344.8 kcal/(h·m·°C) | Copper |
| 0.7595 cal/(s·cm·K) | 273.4 kcal/(h·m·°C) | Gold |
| 0.5661 cal/(s·cm·K) | 203.8 kcal/(h·m·°C) | Aluminum |
| 0.1242 cal/(s·cm·K) | 44.71 kcal/(h·m·°C) | Cast iron |
| 0.1194 cal/(s·cm·K) | 42.99 kcal/(h·m·°C) | Steel (carbon) |
| 0.005971 cal/(s·cm·K) | 2.15 kcal/(h·m·°C) | Marble |
| 0.00406 cal/(s·cm·K) | 1.462 kcal/(h·m·°C) | Concrete |
| 0.002388 cal/(s·cm·K) | 0.8598 kcal/(h·m·°C) | Glass |
| 0.001433 cal/(s·cm·K) | 0.5159 kcal/(h·m·°C) | Water (20°C) |
| 0.000406 cal/(s·cm·K) | 0.1462 kcal/(h·m·°C) | Wood (oak) |
| 9.554e-05 cal/(s·cm·K) | 0.03439 kcal/(h·m·°C) | Fiberglass batt |
| 6.210e-05 cal/(s·cm·K) | 0.02236 kcal/(h·m·°C) | Air (25°C) |
| 3.583e-05 cal/(s·cm·K) | 0.0129 kcal/(h·m·°C) | Aerogel |
1 cal/(s·cm·K) = 360 kcal/(h·m·°C).
Copper ≈ 401 W/(m·K). Steel ≈ 50 W/(m·K). Glass ≈ 1 W/(m·K). Air ≈ 0.026 W/(m·K).
Multiply result by 0.002778 to recover the original cal/(s·cm·K) value.
Specifies insulation and wall assembly thermal conductivity in W/(m·K) for energy compliance calculations.
Uses BTU/(h·ft·°F) for US building code compliance and W/(m·K) for metric heat transfer calculations.
Compares thermal conductivity of metals, polymers, and composites in W/(m·K) for thermal management design.
Selects thermal interface materials and heatsinks using conductivity data in W/(m·K).
Designs heat exchangers using shell and tube thermal conductivity specifications in W/(m·K).
Measures and reports thermal conductivity of novel materials (graphene, CNTs, aerogels) in W/(m·K) or kW/(m·K).
Calorie per second per centimeter per kelvin (cal/(s·cm·K)) is the CGS unit of thermal conductivity, equal to 418.68 W/(m·K). It was the standard in pre-SI physics and chemistry literature.
Cal/(s·cm·K) appears in older scientific handbooks and classic thermodynamics texts. Copper in CGS = 0.923 cal/(s·cm·K); iron = 0.179 cal/(s·cm·K); water = 0.00143 cal/(s·cm·K). The unit is rarely used in modern practice.
Interesting fact: The CGS unit cal/(s·cm·K) is 418.68× larger than W/(m·K) — so most materials have very small values in CGS. Water at 0.00143 cal/(s·cm·K) demonstrates why the CGS unit became impractical for most engineering applications.
Kilocalorie per hour per meter per degree Celsius (kcal/(h·m·°C)) equals 1.163 W/(m·K). It was used in older European engineering texts and some industrial specifications, particularly in countries using kcal for thermal calculations before SI adoption.
kcal/(h·m·°C) appears in older continental European building physics, heat exchanger design manuals, and some Russian and Eastern European engineering standards. Steel ≈ 43 kcal/(h·m·°C); concrete ≈ 1.46 kcal/(h·m·°C); air ≈ 0.022 kcal/(h·m·°C).
Interesting fact: The kcal was the standard energy unit in continental European engineering before SI adoption in the 1970s–1980s. Many countries' building codes still include kcal-based thermal conductivity values in older editions, requiring conversion when working with modern SI specifications.
Thermal conductivity measures how readily a material conducts heat. The SI unit W/(m·K) is universal in science; US building codes use BTU/(h·ft·°F); older European engineering uses kcal/(h·m·°C); CGS physics uses cal/(s·cm·K). Key anchors: air 0.026 W/(m·K), glass 1.0, steel 50, copper 401, diamond 2,200.
Exact factor: 1 cal/(s·cm·K) = 360 kcal/(h·m·°C). Reverse: 1 kcal/(h·m·°C) = 0.002778 cal/(s·cm·K).
All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.