Calculators
Air calculators
Plain-English calculators for the most common air and HVAC math. We're polishing each one — drop your email on the home page to be notified.
Coming soon
Return air size calculator
Estimate the right return grille and duct size for a given CFM and noise target.
Coming soon
Room CFM calculator
Calculate the airflow each room actually needs based on size, use, and load.
Coming soon
Filter pressure drop estimator
See how MERV and face velocity affect static pressure and airflow.
Coming soon
Air changes per hour calculator
Convert room volume and CFM into ACH so you can size ventilation properly.
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