The Duct Sizer App designed based on surveying the needs of engineers.
Units can be changed from Imperial to S.I

This is a much faster and versatile equivalent of the duct sizing charts provided by top HVAC manufacturers.

In Design Mode: Get a range of suitable duct sizes by inputting either the maximum friction rate or maximum velocity. The App will provide a list of suitable rectangular and circular ducts as well as resulting friction rates and velocities

In Sizing Mode: Just like a Ductulator, Adjust the duct dimensions and air flow rates, while checking the resulting friction rate and velocity which update automatically. The Sizing mode is typically used to analyze existing duct systems, and was added upon the request of users' feedback.

Calculations are based on standard air 0.075 lb/ft3 (1.2 kg/m3) in clean galvanized steel duct.

Any feedback is welcome, and will be the basis for future updates.