The ASHRAE Duct Fitting Database (DFDB) for the iPhone and iPad is now compatible with iOS 14 and iPhone 12 Pro.

The ASHRAE DFDB app allows you to perform pressure loss calculations for all 240+ ASHRAE duct fittings in both IP and SI units. Features include dynamic illustrations of each design, and the ability to share reports and spreadsheets through email.

This app is based upon the popular ASHRAE Duct Fitting Database desktop and web applications. The advantages of this mobile app are that you can easily use it out in the field to do quick duct pressure loss calculations, the inputs can be adjusted by touch, and installation is automatic.

The following is a partial list of features:

1. You can create individual projects, each with unique input values and results.

2. Each fitting has its own custom set of input parameters and results.

3. You can easily change the minimum and maximum allowable values for all input parameters.

4. It includes a useful search feature that allows you to type in a partial or full fitting code name to quickly retrieve it.

5. It allows you to display and email two types of reports. The app reports also include a spreadsheet attachment that you can open on your desktop computer to do further analysis.

6. The app displays inputs and results in both IP and SI units.

7. Works on both the iPhone and iPad and adjusts its user interface according to the proper size screen.

The ASHRAE Duct Fitting Database application was designed by Carmel Software Corporation exclusively for ASHRAE.

What’s New

Version 5.9

1. Fixed issues with the input parameters for the CD6-1, ED1-2, and ED1-3 fittings.

Ratings and Reviews

Ardikhla ,


This expensive app is a great idea that was executed horribly. The program crashes often on certain fittings - so much so that I don't use it anymore.

AirConReseller1001 ,

Useful app with lots of data

This is a very useful app with lots of coefficient data for almost all of the ASHRAE fittings (230+). I noticed that a couple are missing, but I did talk w/Carmel and they are releasing an update in January 2012 that will include all the remaining fittings, including the ED5's and more.

I love that I can email the fitting data with picture. Very handy. Look forward to the newest update soon.

Mechengineer1000 ,

Great app

I've been using the DFDB desktop app for years and it's been a great tool. Now, this DFDB mobile app allows me to do quick fitting pressure loss calcs out in the field, and then email the results back to the office for further analysis. It's amazing that the entire database of 200 or so fittings is in this little app.

Great job!

App Privacy

The developer, ASHRAE, Inc., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

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

More By This Developer

You Might Also Like