Dust Collector Sizing Calculator
Dust collector sizing begins with the airflow required at open tool ports and the velocity needed to keep chips and dust moving through the duct. This path opens the CFM calculator for the first sizing screen.
Start with CFM
Use port diameter and target transport velocity to screen branch airflow before looking at collector horsepower or advertised CFM.
Main duct velocity
The working calculator recomputes velocity in the entered main duct diameter so oversized mains with low airflow are visible.
Fan curve next
A dust collector that advertises enough free-air CFM may still miss the target after filters, cyclone loss, elbows and flex hose. Use fan-curve data for the final buy decision.
Frequently asked questions
Is this enough to buy a collector?
No. It is the first airflow screen. Compare the result to static pressure and manufacturer fan curves before buying.
Should every branch be counted?
Count only branches expected to be open at the same time. Blast-gated one-machine shops usually use one active branch.
Related pages
- Dust collector CFM calculator - working airflow and velocity calculator.
- Dust collection CFM calculator - CFM-focused search path for the same workflow.
- Duct size calculator - general duct area and velocity calculator.
- Static pressure calculator - pressure-loss follow-up after sizing airflow.