Estimate conductivity from thermal impedance and geometry. Handle units, exports, and plotted sensitivity curves easily. Support better material selection during demanding engineering design reviews.
k = L / (R × A)
Here, k is thermal conductivity in W/m·K, L is thickness in meters, R is thermal impedance in K/W, and A is heat flow area in square meters.
When thermal impedance is not given directly, the calculator first uses R = ΔT / Q. Here, ΔT is the temperature rise and Q is heat flow in watts.
The calculator also reports thermal resistivity, area-normalized resistance, total conductance, and the equivalent heat transfer coefficient for a more complete engineering view.
| Case | Thickness | Area | Thermal Impedance | Calculated Conductivity |
|---|---|---|---|---|
| TIM Pad | 1.5 mm | 25 cm² | 0.12 K/W | 5.00 W/m·K |
| Ceramic Spacer | 3.0 mm | 9 cm² | 0.833 K/W | 4.00 W/m·K |
| Polymer Sheet | 2.0 mm | 16 cm² | 0.625 K/W | 2.00 W/m·K |
Thermal impedance is often measured at the part or interface level. Thermal conductivity is a material property. Converting one into the other only makes sense when thickness and effective area are known with reasonable confidence.
Area selection matters. A larger area lowers total thermal impedance for the same material and thickness. Thickness matters too. A thicker layer raises resistance and lowers conductance.
This calculator is useful for thermal interface materials, pads, sheets, spacers, insulating layers, and simple one-dimensional heat flow approximations. It is less suitable for spreading resistance, anisotropic media, or complex transient cases.
It converts thermal impedance into thermal conductivity when thickness and area are known. It can also derive thermal impedance first from temperature rise and heat flow.
No. Thermal impedance describes resistance for a specific part and geometry. Thermal conductivity describes the material itself. Geometry links the two values.
Heat spreads through an area. A larger cross-sectional area lowers resistance. A smaller area raises resistance for the same material and thickness.
Yes. A temperature difference in degrees Celsius is numerically equal to the same difference in kelvin, so either unit works for ΔT.
Use direct area when the effective heat transfer area is already known from a drawing, data sheet, or a previous thermal model.
Use rectangle or circle inputs when area is easier to describe from dimensions. The calculator converts those dimensions into the required area automatically.
Not directly. A multilayer stack needs combined thermal resistance across all layers. This calculator is best for one equivalent layer at a time.
Common causes are wrong units, incorrect effective area, contact resistance, spreading effects, or using a total device impedance as if it were a pure material property.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.