Size your supply and return ductwork based on room-by-room CFM requirements. Use this after running a load calculation to make sure the duct system can actually deliver the airflow the equipment needs.
Duct Design Calculator
Size your supply and return ductwork based on Manual D principles
1Step 1Rooms
2Step 2Equipment
3Step 3Results
Smart Parse
Paste Property Description
Drop in a property description with sq ft and bedroom count and we'll auto-fill the room layout for you.
— or start from a template —
Quick fill
Room nameSq ftType
Total square footage0 sq ft
Sizing follows Manual D friction rate methodology. Actual installations should account for fitting equivalent lengths and total external static pressure.
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