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Thermodynamics Calculators

Heat Transfer Calculator (Conduction)

Conductive heat flow through a wall or material layer from conductivity, area, thickness and ΔT.

Enter values

Insulation 0.04, brick 0.7, glass 1.0, steel 50

Results update as you type.

Result

Heat flow

160 W

Per day
3.84 kWh
R-value of the layer
2.5 m²·K/W
U-value
0.4 W/(m²·K)

About the Heat Transfer Calculator (Conduction)

Conductive heat flow through a wall or material layer from conductivity, area, thickness and ΔT.

Also known as: conduction calculator, fourier law, heat flow through wall, thermal conduction.

How to use this calculator

  1. Enter thermal conductivity, area, temperature difference, thickness.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Formula

Fourier's law: Q = k·A·ΔT / d

Worked example

Using the values pre-filled in the calculator above:

  • Thermal conductivity = 0.04 W/(m·K)
  • Area = 20 m²
  • Temperature difference = 20 K
  • Thickness = 0.1 m

the calculator returns:

  • Heat flow: 160 W
  • Per day: 3.84 kWh
  • R-value of the layer: 2.5 m²·K/W
  • U-value: 0.4 W/(m²·K)