In early versions of Mac OS, users looking for a way to quickly rename multiple files simultaneously (commonly referred to as batch renaming) had to use the command line or download and install a third-party tool dedicated to the task.
Since OS X Yosemite however, Apple has integrated several useful batch renaming capabilities directly into Finder.
To rename several files of the same kind on your Mac at once, follow the steps below. In our example we’re going to be batch renaming some photos.
- Open a Finder window and locate the files you want to rename.
- Drag a selection box over the files with your mouse or hold the Shift key and click them one by one.
Read more at MacRumors.com