An app as easy to use as the paper Duct calculator with all the same functionality plus additional offset calculations. Simple Duct Calculator Deluxe does all basic calculations with simplicity in mind from the start all within a beautiful sleek interface.

Duct Sizing & Calculator portion includes calculating:
- Equivalent duct sizes
* Rectangular to Round and Equivalent Rectangular Sizes
* Round to Rectangular
* Maximum CFM and Velocity for Duct Size by inches of water per 100'
- CFM calculations
- Round & Rectangular Duct Size Equivalents
- Change friction

Offset portion includes:
- Double Elbow Offsetting
- 3 Piece Elbow Offsetting
- OWL for Field Cut Offsetting



Please E-Mail me for problems, comments and suggestions/future features.


Calculation formulas for air used are based upon SMACNA standards and for offsets algebra and trigonometry.

Currently sizing and calculations are only in SAE/Imperial but a Metric update is planned.

Reference herein to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not constitute or imply its endorsement, recommendation, or favoring.