Thermal Conductivity Converter

The Thermal Conductivity Converter by MultiCalculators is an essential tool for engineers, material scientists, HVAC specialists, and students working with heat transfer. Thermal conductivity (often denoted k, λ, or κ) measures a material's ability to conduct heat. It appears in Fourier's law and is critical for designing insulation, heat exchangers, electronic cooling systems, and building envelopes. Our converter supports the most widely used units: the SI unit watt per meter-kelvin (W/(m·K)), the imperial unit BTU·inch per hour·square foot·°F (often used for insulation values in the US), BTU per hour·foot·°F, kilocalorie per hour·meter·°C (still common in some engineering fields), and cal per second·cm·°C (cgs system).

Conversions among these units are not trivial; they involve mixed dimensions of length, time, temperature, and energy. Our tool uses precise, internationally accepted conversion factors. For example, 1 BTU·in/(hr·ft²·°F) equals 0.1441314 W/(m·K). The conversion between BTU/(hr·ft·°F) and W/(m·K) is 1 BTU/(hr·ft·°F) = 1.730735 W/(m·K). We also include kcal/(hr·m·°C) which is numerically identical to 1.163 W/(m·K) (since 1 kcal = 4186.8 J, but in thermal conductivity, the commonly used factor is 1 kcal/(hr·m·°C) = 1.163 W/(m·K) exactly). The cgs unit cal/(s·cm·°C) converts to 418.68 W/(m·K).

This converter updates instantly as you type or change units. The swap button lets you reverse the conversion direction, which is helpful when comparing material specifications from different standards. Whether you are evaluating insulation materials (k‑values), designing a heat sink, or performing research, you can rely on the accuracy of our calculations. The interface is fully responsive, ensuring smooth operation on desktops, tablets, and smartphones.

We've also included J/(s·m·K) as a synonym for W/(m·K) to avoid confusion. If you work with cryogenics or high-temperature processes, these conversions are vital. The tool uses double-precision floating-point internally and presents results with up to six decimal places, balancing readability and precision. You can copy the exact value from the readonly “To” field.

MultiCalculators is committed to providing high-quality, free utilities. We hope this Thermal Conductivity Converter saves you time and eliminates manual errors. If you need additional units or have suggestions, please visit our Contact page. Convert with confidence!