Skip to content

CFM Calculator

Estimate room airflow in CFM from length, width, ceiling height, and air changes per hour. Works in feet or meters and shows room volume in ft3 and m3.

Dimension unit

Choose the unit that matches the room measurements you will enter below.

Room length

ft

Measure the inside room length, not the exterior wall line.

Room width

ft

Ceiling height

ft

Air changes per hour

ACH

Enter the ACH target from your plan, standard, or equipment requirement.

This form uses the ACH method for one simple rectangular room. It estimates room airflow only and does not add duct friction, filter pressure drop, or equipment safety factors.

Powered by CalcTide