Thermal Conductivity Converter

Convert thermal conductivity between W/(m·K), mW/(m·K), W/(cm·K), kcal/(h·m·°C), and International Btu/(h·ft·°F).

Convert instantly

Enter a value and choose the units. Your answer updates as you type.

Value

From

Result

1000 Milliwatt per meter kelvin (mW/(m·K))

Quick reference

Watt per meter kelvin (W/(m·K))1 base units
Milliwatt per meter kelvin (mW/(m·K))0.001 base units
Watt per centimeter kelvin (W/(cm·K))100 base units
International Btu per hour foot Fahrenheit (Btu/(h·ft·°F))1.730734666371391 base units
Kilocalorie per hour meter Celsius (kcal/(h·m·°C))1.162222 base units

About the Thermal Conductivity Converter

Thermal conductivity k measures how readily heat moves through a material and is reported in W/(m·K) for SI engineering. Low values indicate insulation; metals are much higher. This converter uses the International Table BTU and the correct Fahrenheit interval, so 1 Btu/(h·ft·°F) is approximately 1.730735 W/(m·K).

Use a datasheet value to compare insulation, polymers, fluids, or metals—for example, 0.04 W/(m·K) is 40 mW/(m·K). Combine it with Thermal Resistance Converter for a layer's R'' = L/k, or the Heat Flux Density Converter when a temperature gradient is known.

Frequently asked questions

What does thermal conductivity measure?

It measures heat-flow rate through a material for a given temperature gradient, with SI unit W/(m·K).

Is a lower conductivity better insulation?

Yes. A lower k value generally means less heat flows through a layer of the same thickness and area.

How many W/(m·K) are in 1 Btu/(h·ft·°F)?

One International Btu/(h·ft·°F) is approximately 1.730735 W/(m·K).

Take this calculation further

Browse the converters calculators collection for more tools in this subject.

For a related calculation, use Specific Heat Capacity Converter to convert specific heat capacity between J/(kg·K), kJ/(kg·K), cal/(g·°C), and International Btu/(lb·°F). Alternatively, use Thermal Resistance Converter to convert area-normalized thermal resistance between m²·K/W, cm²·K/W, m²·K/kW, and ft²·°F·h per Btu.

For the underlying method, read A Practical Guide to Thermal Conductivity and Insulation.