Fast field calculators for HVAC, Plumbing & Electrical
hvac calculator workflow
Sizing, airflow, duct, and efficiency calculators for quick HVAC planning.
Choose a path based on the decision you need to make: equipment capacity, airflow, or duct performance.
Estimate load, translate to equipment size, then verify airflow support.
Work from required air movement toward duct area and velocity.
Common starting points for quick planning and assumption checks.
Estimate room heating and cooling BTU load from area, ceiling height, insulation, and sun exposure for faster HVAC plann...
Open calculatorConvert conditioned area and insulation assumptions into estimated BTU demand and AC tonnage to shortlist practical cool...
Open calculatorEstimate a mini split BTU range from room size, ceiling height, and climate so technicians and homeowners can choose pra...
Open calculatorUse these groups to move from an initial estimate to the next practical check.
Start here when the question is capacity, equipment class, or comfort planning.
Use these calculators when air changes, CFM targets, or hydronic flow assumptions drive the decision.
Check whether airflow assumptions fit the duct path, area, and pressure-loss context.
Translate capacity units or compare operating cost assumptions.
Estimate room heating and cooling BTU load from area, ceiling height, insulation, and sun exposure for faster HVAC planning and equipment sizing.
Open calculatorConvert conditioned area and insulation assumptions into estimated BTU demand and AC tonnage to shortlist practical cooling capacity options quickly.
Open calculatorEstimate a mini split BTU range from room size, ceiling height, and climate so technicians and homeowners can choose practical equipment faster.
Open calculatorCalculate required airflow CFM from room dimensions and target ACH so HVAC teams can estimate ventilation and comfort airflow requirements quickly.
Open calculatorEstimate round duct diameter from airflow and velocity targets so installers can choose practical branch sizes during early layout and retrofit planning.
Open calculatorEstimate duct pressure loss from run length, fittings, diameter, and airflow so technicians can sanity-check static pressure assumptions quickly.
Open calculatorCompare annual cooling energy use between existing and proposed SEER ratings to estimate operating-cost savings and support upgrade planning.
Open calculatorEstimate required baseboard heater length from room conditions or known BTU load with hydronic and electric output assumptions.
Open calculatorConvert heating and cooling values between BTU/hr, tons, and kW for quick HVAC planning and equipment comparisons.
Open calculatorEstimate total system airflow from equipment tonnage and target CFM per ton for fast HVAC planning checks.
Open calculatorCalculate duct air velocity from CFM and duct dimensions for round or rectangular ducts.
Open calculatorEstimate total equivalent duct length from straight run and fitting counts for early static-pressure checks.
Open calculatorEstimate hydronic flow rate (GPM) from heat load and temperature difference for water-based systems.
Open calculatorHVAC guide
HVAC planning works best when capacity, airflow, and duct assumptions are checked together instead of treated as separate guesses.
HVAC guide
Airflow calculations connect equipment sizing to comfort. This guide explains how CFM targets and duct velocity checks fit together.
Planning guide
This guide shows a repeatable process for turning fast calculator outputs into better field decisions. It is designed for technicians,...
HVAC
A practical approach to AC sizing that balances BTU load assumptions, tonnage, airflow, and comfort outcomes.
HVAC
A simple HVAC translation guide: BTU load, tonnage classes, and when each unit is most useful.
These calculators support early planning and field checks. Final decisions should account for site conditions, adopted local codes, manufacturer data, and licensed trade review where required.