Heat Loss Calculator
Result
Heat Loss630 W
Heat Loss (kW)0.63 kW
Heat Loss (BTU/hr)2,149.65 BTU/hr
Temperature Difference21 °C
↗ Construction
Heat Loss Calculator — free online calculator.
Formula
HeatLoss (W) = Area × U-Value × (T_indoor − T_outdoor)
- Heat Loss Calculator calculates its result from Area, U, Value, T Indoor, T Outdoor. It uses the formula HeatLoss (W) = Area × U-Value × (T_indoor − T_outdoor). Change any input to recalculate the result instantly.
- The main inputs are Surface Area, U-Value, Indoor Temperature, Outdoor Temperature. Enter them in the units and format shown in the calculator.
- Keep measurements and project assumptions consistent before comparing or combining values.
- Changing any input above recalculates the result with the same calculation engine used by this page.
Example: Heat Loss
Inputs
- Surface Area: 100 m²
- U-Value: 0.3 W/m²K
- Indoor Temperature: 21 °C
- Outdoor Temperature: 0 °C
Using Area = 2, U = 3, Value = 4, T Indoor = 5, T Outdoor = 6, the calculated result is 10.
Sample result: Calculating…
Frequently asked questions
What does the Heat Loss calculate?
Heat Loss Calculator — free online calculator.
Which values should I enter?
Enter Surface Area, U-Value, Indoor Temperature, Outdoor Temperature using the units and format shown beside each field.
What formula does this calculator use?
The calculator uses the following relationship: HeatLoss (W) = Area × U-Value × (T_indoor − T_outdoor).
Why might my result differ from another source?
Results can differ when another source uses different units, rounding rules, conventions or assumptions. Compare the inputs and definitions before comparing results.
Does the result update automatically?
Yes. Changing an input updates the result using the same calculation engine shown on this page.