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...
Energy Converter between J, kJ, cal, kcal, kWh, BTU, and eV
Convert energy between joules, kilojoules, calories, kilocalories, kilowatt-hours, BTU, and electronvolts with a joule-based calculator, examples, and context.
Hot Tub Heating Time Calculator | Estimate Spa Warm-Up Time
Estimate hot tub warm-up time from water volume, heater power, and start and target temperature, with a real-world efficiency factor, energy use, and cost.
R-Value to U-Value Converter - Compare Insulation Performance
Convert R-value to U-value and back, add SI units and heat flux, then build a layered wall assembly with framing factor to beat a code U-factor target.
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.
Closed-Loop Geothermal Ground Loop Pipe Length Calculator
Estimate total closed-loop geothermal pipe length from design load, soil conductivity, allowable loop-to-ground temperature difference, and a design factor.
All calculators in this cluster
Browse 30 calculators matched to this topic, or return to the Science category.
Absolute Humidity Calculator: Temperature & Relative Humidity to g/m³
Convert air temperature and relative humidity into absolute humidity in g/m³, with dew point, mixing ratio, specific humidity, and 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, Saturated and Stability
Compute the dry adiabatic lapse rate from g/cp, the true saturated rate that varies with temperature and pressure, and classify atmospheric stability.
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.
Closed-Loop Geothermal Ground Loop Pipe Length Calculator
Estimate total closed-loop geothermal pipe length from design load, soil conductivity, allowable loop-to-ground temperature difference, and a design factor.
Cylindrical Wall Heat Conduction Calculator | Pipe and Insulation Heat Loss
Estimate steady radial heat loss through a cylindrical wall such as a pipe, tube, or insulated vessel. Solve for Q, k, L, r₁, r₂, or ΔT 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 | Molar Heat Capacity from Temperature
Estimate a solid lattice heat capacity from temperature and Debye temperature with a numerical Debye-model integral.
Dual-Fuel Heat Pump Balance Point Planner | Find the Furnace Switchover Temperature
Estimate the outdoor switchover temperature for a dual-fuel heat pump by comparing heating load, COP, backup fuel cost, and emissions.
Earth Tube Cooling Length Calculator
Estimate the length of buried air tubes needed to cool incoming ventilation air using ground temperature.
Energy Converter between J, kJ, cal, kcal, kWh, BTU, and eV
Convert energy between joules, kilojoules, calories, kilocalories, kilowatt-hours, BTU, and electronvolts with a joule-based calculator, examples, and context.
Engine Coolant Mix Ratio Calculator (Antifreeze to Water)
Find the lowest ethylene or propylene glycol volume percent that protects your engine to a target temperature, plus cap-pressure boil-over and mix volumes.
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.
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 - 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 for Seasonal COP Impact
Estimate how repeated defrost cycles lower seasonal COP in an air-source heat pump, and compare cycle frequency, duration, and penalty factor to gauge the winter efficiency hit.
Hot Tub Heating Time Calculator | Estimate Spa Warm-Up Time
Estimate hot tub warm-up time from water volume, heater power, and start and target temperature, with a real-world efficiency factor, energy use, and cost.
Hot Water Heating Cost Calculator - Energy Use and Bill Impact
Work out the kWh, therms, Ccf or propane gallons and the dollars needed to heat any volume of water from your water heater UEF and your utility energy 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 - Round Duct Diameter from CFM
Calculate an estimated round HVAC duct diameter from airflow in CFM and duct-run length, using an 800 FPM target and a length adjustment.
IRA Home Energy Rebate Stacking Planner for HOMES, HEEHR, and 25C Credits
Model stacked home-electrification incentives by combining HOMES rebates, HEEHR point-of-sale discounts, Section 25C tax credits, and sample state programs for heat pumps, insulation, panel work, windows, and more.
Nuclear Decay Heat Calculator - Estimate Residual Heat After Shutdown
Estimate residual reactor heat after shutdown with a simple power-law decay model, editable coefficient and exponent inputs, and 24-hour and 7-day reference values for classroom comparison.
Polytropic Process Pressure, Work, and Temperature Ratio Calculator
Calculate final pressure, boundary work, and temperature ratio for an ideal-gas polytropic process from its initial pressure, initial volume, final volume, and exponent.
R-Value to U-Value Converter - Compare Insulation Performance
Convert R-value to U-value and back, add SI units and heat flux, then build a layered wall assembly with framing factor to beat a code U-factor target.
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)...