Ventilation CFM calculator

Room Ventilation CFM Calculator

Calculate planning CFM from square feet, ceiling height, ACH, room use, source condition, and duct path for offices, classrooms, restaurant support rooms, storage rooms, gyms, and other commercial rooms before equipment selection.

Room Ventilation CFM Calculator: Estimate ventilation CFM from room area, ceiling height, air-change target, room use, source conditions, duct route, filters, and service access. Use the result to compare fresh air, exhaust, inline, and cabinet fan paths; it is not a code design.

Updated 2026-07-06
Area square feet ACH air-change target CFM planning airflow Duct route review

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The same CFM can lead to different products depending on whether the room needs fresh air, exhaust, source control, or ducted support.

Carry Forward

Fresh air target

Occupied rooms often point CFM toward ERV or fresh-air equipment selection.

Capture occupancy and filter expectations.

Ventilation CFM should be paired with room use, source, and duct path before selecting equipment.