Physics
Instant, private, and free
Heat Transfer Calculator.
Calculate heat transferred with an explicit basic, conduction, convection, or radiation model.
Set your values
Results update as you type.
Results update automatically as you type.
Educational model. Inputs and assumptions are explicit; verify engineering or scientific decisions independently.
Use Cases
Educational Physics Problems
Solve textbook problems involving heat transfer. Select the appropriate model (basic, conduction, convection, or radiation) and input the given values to find the heat transferred.
Example: Calculate the heat needed to raise 2 kg of water from 20°C to 80°C using the basic model.
Preliminary Engineering Estimates
Quickly estimate heat loss or gain in simple systems like insulation, heat exchangers, or electronic cooling. Use the conduction or convection models to get a rough number before detailed analysis.
Example: Estimate heat loss through a 0.1 m thick wall with a temperature difference of 30°C using the conduction model.
Frequently Asked Questions
- What is the Heat Transfer Calculator used for?
- This calculator computes the amount of heat transferred in various modes: basic (using Q = mcΔT), conduction (Fourier's law), convection (Newton's law of cooling), and radiation (Stefan-Boltzmann law). It's useful for students, engineers, and hobbyists to quickly estimate heat flow in different scenarios.
- What are the four models in this calculator?
- The calculator offers four models: basic (sensible heat change), conduction (heat through a material), convection (heat transfer between a surface and a fluid), and radiation (heat emitted via electromagnetic waves). Each model uses its own formula and requires specific inputs.
- Can I use this calculator for real-world engineering design?
- This tool provides estimates for educational and preliminary analysis. For actual engineering design, you should consult detailed standards and consider factors like material properties, geometry, and environmental conditions. Always verify with professional analysis.
Tips & Common Mistakes
Tips
- Ensure all units are consistent (e.g., use meters for length, Kelvin or Celsius for temperature difference, and watts for power).
- For conduction, use the thermal conductivity (k) of the material; for convection, use the heat transfer coefficient (h) which depends on fluid and flow conditions.
- For radiation, remember to use absolute temperature (Kelvin) and set emissivity between 0 and 1.
- Double-check your inputs: a small error in temperature difference can significantly affect the result.
Common Mistakes to Avoid
- Using Celsius instead of Kelvin for radiation calculations – always convert to absolute temperature.
- Confusing heat transfer rate (W) with total heat energy (J) – the calculator may output either; check the model's formula.
- Forgetting to include the area in conduction or convection calculations – area is a key factor.
Last updated: August 13, 2026