One forum member mentioned those numbers might be different for exterior.

Rough opening for 32 inch exterior door. Insulated door curtain for french & patio sliding doors up to 72 x 80 inch new. Rough opening for 32″, 28″, 30″, 24″, 34″ & 36 inch door. We've provided a door rough opening guide & chart to help customers & contractors determine proper rough opening for any given metal frame.

I have a rough opening of 33 1/2 inches for a doorway. Now all you need to know is how to properly frame your door rough opening. Articles i read talk about needing 34 inches for a 32 inch door.

All you need to know to measure for your new murphy door.www.themurphydoor.com 7 rows a framing rough opening size for a 32 inch size door will be 34” in width (after adding 2”. As you can see, the standard exterior door size rough opening is a full 2 ¼ inches wider than 36.

What is the rough opening on a 36 inch exterior door? 2’6” x 6’8” rough opening size: Standard door heights are 6/6 (78”) and 6/8 (80”).

That means a 32x80 inch door needs a 34x82 inch opening. Is it the same for exterior doors?