Duct Size Calculator
Convert airflow + target velocity into round & rectangular duct sizes
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Filter Face Velocity
Airflow
Airflow Unit
CFM
m³/h
L/s
Target Velocity
Velocity Unit
m/s
fpm
Rectangular Aspect Preference
1:1 (square)
1.5:1
2:1
3:1
4:1
Enter airflow + velocity to get duct sizes.