This duct sizing app was created for HVAC design professionals who might normally use a "ductulator" to select an duct sizes.

The app goes beyond simply calculating velocity, friction, or volume; It also offers a list of every even sized duct that meet the design criteria for the user to review and consideration at various aspect ratios.

The app features a highly intuitive interface which allows the user to easily adjust values with precision (without the use of cumbersome "slider" controls), or alternatively to enter the values directly with a keypad interface.

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What’s New

Version 1.3

updated for 64 bit compatibility

Ratings and Reviews

5.0 out of 5
1 Rating

1 Rating

A Caveman ,

Does exactly what it claims.

5 stars! This app does exactly what it advertises: Solves for velocity friction or volume (pick any two to input).
And it lists round, square, and every even size duct after that, which could be a lot depending on the variables. Definitely worth the small price.

Chadwick 78 ,

Me. Chadwick 78

Very accurate and helpful to use in the field, also saves time compared to the wheel.

Ritchiec711 ,

Excellent App for quick sizing

Excellent for quick sizing and decision making, well worth the purchase. Only one constructive suggestion the ability to limit the list of rectangular sizes by aspect ratio 1:1, 3:1 , etc


Alan Cave
31 MB

Requires iOS 9.1 or later. Compatible with iPhone, iPad, and iPod touch.



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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