Reply To: GREP style, i want to add "," in numbers 3454342? 3,454,342

This was discussed on another thread here:

Add comma to numbers

The quick answer is there is no “generic” way to do this for thousands, millions, billions, and more… you need to run more than one find/change.

Also, Peter Spier wrote on the Adobe forums: “First find \d(?=\d{6}\.\d) and change to $0, which will add the comma for the millions, then find \d(?=\d{3}\.\d) and change to $0, to add the comma for the thousands. These expressions work only if there is a decimal number”

However, there is also a free script here: https://www.id-extras.com/script-to-format-long-numbers