Science cluster
Heat & Thermodynamics Calculators
Work out heat transfer, insulation, HVAC loads, and thermodynamic cycle efficiency for heating, cooling, and engines.
Top calculators
A short starting set for the most common heat & thermodynamics calculators workflows.
Residential Electrical Load Calculator & Breaker Sizing Tool
Estimate household electrical demand, compare it with your service size, and review conservative breaker and panel upgrade guidance for common residential loads.
HVAC BTU Calculator for System Sizing | Estimate Cooling Tons
Estimate HVAC cooling capacity in BTU/hr and tons for a room, house, or office using square footage, climate, insulation, sun exposure, and internal heat gains. Compare sizing assumptions and review practical limits.
Specific Heat Calculator - Heat Energy From Temperature Rise
Calculate heat energy using Q = mcΔT. Enter mass, specific heat capacity, and temperature change to find the heat required or released when a material warms...
Dual-Fuel Heat Pump Balance Point Planner - Optimize Switchover Temperature
Determine the economic balance point for dual-fuel heat pump systems by comparing electricity and backup fuel costs across outdoor temperatures.
Energy Converter (J, kJ, cal, kcal, kWh, BTU, eV)
Convert energy between joules (J), kilojoules (kJ), calories (cal), kilocalories (kcal), kilowatt-hours (kWh), BTU, and electronvolts (eV). Includes formula, worked examples, assumptions, practical context, and an optional energy-conversion mini-game.
Hot Tub Heating Time Calculator | Estimate Spa Warm-Up Time
Estimate how long it takes to heat a hot tub based on water volume, heater power, starting temperature, target temperature, efficiency, and electricity rate. Learn the formula, assumptions, and practical ways to interpret your spa warm-up time.
R-Value to U-Value Converter - Compare Insulation Performance
Convert insulation R-value to U-value or vice versa to understand heat flow through walls, roofs, and windows.
Server Rack Cooling Airflow Calculator (CFM, m³/s, BTU/hr)
Estimate the airflow a server rack needs from its power and allowable temperature rise. Get results in m³/s, CFM, and BTU/hr for quick data center cooling planning.
All calculators in this cluster
Browse 30 calculators matched to this topic, or return to the Science category.
Absolute Humidity Calculator - g/m³ from Temperature & RH
Calculate absolute humidity in g/m³ from temperature and relative humidity, plus dew point, mixing ratio, and specific humidity with a saturation-curve chart.
Adiabatic Compression Temperature Calculator | Final Gas Temperature
Estimate final gas temperature after ideal adiabatic compression from initial temperature, pressure ratio, and heat capacity ratio.
Adiabatic Lapse Rate Calculator (Dry vs Moist)
Calculate the estimated air-parcel temperature after an altitude change using dry (9.8 °C/km) or moist (6.5 °C/km) adiabatic lapse rate assumptions. Includes a worked example, formulas, assumptions, and interpretation tips.
Atmospheric Reentry Heating Calculator - Stagnation Point Heat Flux
Estimate convective heat flux on a spacecraft's nose during atmospheric reentry using the Sutton–Graves relation.
Cylindrical Wall Heat Conduction Calculator | Solve for Q, k, ΔT, Radius, or Length
Free cylindrical wall heat conduction calculator for steady radial heat flow through a pipe, tube, or insulated cylinder. Solve for heat transfer rate Q, thermal conductivity k, cylinder length, inner or outer radius, or temperature difference with the logarithmic cylindrical conduction equation.
Data Center Waste Heat Reuse Calculator | Recoverable Heat and Annual Value
Estimate how much heat a data center can recover, how much nearby heating demand it can cover, and the annual value of reusing that waste heat.
Debye Specific Heat Calculator - Lattice Vibrations at Low Temperature
Explore the Debye model for solids and compute the specific heat from the Debye temperature and actual temperature.
Dual-Fuel Heat Pump Balance Point Planner - Optimize Switchover Temperature
Determine the economic balance point for dual-fuel heat pump systems by comparing electricity and backup fuel costs across outdoor temperatures.
Earth Tube Cooling Length Calculator
Estimate the length of buried air tubes needed to cool incoming ventilation air using ground temperature.
Energy Converter (J, kJ, cal, kcal, kWh, BTU, eV)
Convert energy between joules (J), kilojoules (kJ), calories (cal), kilocalories (kcal), kilowatt-hours (kWh), BTU, and electronvolts (eV). Includes formula, worked examples, assumptions, practical context, and an optional energy-conversion mini-game.
Engine Coolant Mix Ratio Calculator (Antifreeze to Water)
Calculate an engine coolant (ethylene glycol antifreeze + water) mix ratio based on your minimum ambient temperature and a safety margin. Includes freeze/boil point estimates, a worked example, assumptions, and a reference table.
Geothermal Borehole Spacing Thermal Interference Estimator
Estimate geothermal borehole thermal interference, entering fluid temperature limits, and spacing needs from seasonal load, run hours, depth, conductivity, and allowable temperature inputs.
Geothermal Ground Loop Length Calculator
Estimate closed-loop geothermal ground loop length from design load, soil thermal conductivity, and allowable ΔT. Outputs total pipe length in meters/feet (p...
Heat of Fusion Calculator - Phase Change Energy
Estimate the thermal energy required to melt a substance using its mass and specific heat of fusion. Learn how the latent heat equation applies to ice, metals, and more.
Heat of Vaporization Calculator | Liquid-to-Vapor Energy from Mass and Latent Heat
Estimate the energy needed to vaporize a liquid from its mass and latent heat, with results in kJ, BTU, and kWh plus an optional heat-of-vaporization mini-game.
Heat Pump Defrost Efficiency Loss Calculator
Estimate the seasonal efficiency reduction in air-source heat pumps caused by defrost cycles and assess the likelihood of major energy penalties.
Hot Tub Heating Time Calculator | Estimate Spa Warm-Up Time
Estimate how long it takes to heat a hot tub based on water volume, heater power, starting temperature, target temperature, efficiency, and electricity rate. Learn the formula, assumptions, and practical ways to interpret your spa warm-up time.
Hot Water Heating Cost Calculator - Estimate Energy Expense
Estimate the energy in kWh and cost required to heat water based on volume, temperature rise, heater efficiency, and electricity price.
HVAC BTU Calculator for System Sizing | Estimate Cooling Tons
Estimate HVAC cooling capacity in BTU/hr and tons for a room, house, or office using square footage, climate, insulation, sun exposure, and internal heat gains. Compare sizing assumptions and review practical limits.
HVAC Duct Size Calculator - Choose the Right Diameter
Estimate the proper duct diameter for heating and cooling systems using airflow (CFM) and duct length. Improve efficiency and reduce noise.
IRA Home Energy Rebate Stacking Planner
Stack HOMES, HEEHR, federal credits, and state incentives for heat pumps, insulation, and more to plan your upgrade budget.
Nuclear Decay Heat Calculator - Estimate Residual Reactor Power
Approximate the decay heat power from spent nuclear fuel after shutdown using a simple empirical formula.
Polytropic Process Calculator
Solve gas relationships and work for a polytropic process using initial state, final volume, and polytropic exponent.
R-Value to U-Value Converter - Compare Insulation Performance
Convert insulation R-value to U-value or vice versa to understand heat flow through walls, roofs, and windows.
Residential Electrical Load Calculator & Breaker Sizing Tool
Estimate household electrical demand, compare it with your service size, and review conservative breaker and panel upgrade guidance for common residential loads.
Server Rack Cooling Airflow Calculator (CFM, m³/s, BTU/hr)
Estimate the airflow a server rack needs from its power and allowable temperature rise. Get results in m³/s, CFM, and BTU/hr for quick data center cooling planning.
Shower vs Bath Water, Energy, and Cost Calculator
Compare a shower and a bath using your own flow rate, duration, tub volume, temperature rise, heater efficiency, and energy price to estimate water use, heating energy, and cost.
Specific Heat Calculator - Heat Energy From Temperature Rise
Calculate heat energy using Q = mcΔT. Enter mass, specific heat capacity, and temperature change to find the heat required or released when a material warms...
Water Boiling Time Calculator | Estimate Energy and Heating Time
Estimate how long it takes to heat water to a target temperature using water volume, start and end temperature, heater power, and efficiency.
Window Heat Loss Savings Calculator – Estimate Window Energy & Cost...
Estimate how much upgrading your windows can cut annual heat loss and heating bills. Compare old vs new U-factors, window area, climate (heating degree days)...