Start with the physical question
- Use Heat Energy when a material changes temperature without a phase change.
- Use Heat Conduction for a steady one-dimensional estimate through a known area, material and thickness.
- Use Thermal Expansion when the design concern is free change in length caused by temperature.
- Use the dimensionless tools before selecting a transient or convection correlation.
Live calculators
- Sensible Heat Rate CalculatorCalculate fluid heating or cooling rate from mass flow, specific heat and temperature change.
- Convective Heat Transfer CalculatorCalculate Q = h A ΔT from a stated convection coefficient, area and surface-to-fluid temperature difference.
- Radiative Heat Transfer CalculatorEstimate net Stefan-Boltzmann radiation between a surface and large uniform surroundings.
- Heat Loss CalculatorEstimate conductive heat loss and period energy from a U-value, surface area and temperature difference.
- LMTD Heat Exchanger CalculatorCalculate log mean temperature difference and Q = U A ΔTlm for a stated parallel-flow or counterflow profile.
- Thermal Resistance & U-value CalculatorBuild a material-layer stack and calculate its layer-only R-value and U-value.
- Heat Energy CalculatorSolve sensible heat, mass, specific heat or temperature change using Q = m x c x ΔT.
- Heat Conduction CalculatorEstimate steady one-dimensional conduction rate through a stated material and thickness.
- Thermal Expansion CalculatorEstimate free linear length change caused by a temperature change.
- Elastic Elongation CalculatorEstimate axial stress, strain and elastic length change from a stated load and material modulus.
- Biot Number CalculatorScreen internal versus surface thermal resistance before using a lumped transient model.
- Fourier Number CalculatorCalculate dimensionless time for transient-conduction screening.
- Nusselt Number CalculatorRelate convection coefficient, characteristic length and thermal conductivity.
Important limits
These tools are first-pass calculations. They do not replace a full thermal model with radiation, changing properties, contact resistance, phase change, multidimensional geometry, thermal stress or code-required safety margins. State the material condition, temperature range and boundary conditions before using a result for design.