HVAC

BTU, tonnage, and airflow — rule-of-thumb sizing for AC, heat, and ventilation.

8 calculators
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Room BTUCooling and heating BTU by roomMOST USED →Mini-split sizingRight-size a ductless headOPEN →AC tonnageTons of cooling for a homeOPEN →
All HVAC calculators
Room BTUCooling and heating BTU by roomMini-split sizingRight-size a ductless headAC tonnageTons of cooling for a homeFurnace sizingDehumidifier sizingCeiling fan CFM & sizeTankless water heater sizingDuct CFM helper
Rule-of-thumb sizing — a Manual J calculation by a professional is definitive.