Mac: If you have a group of files you need to rename, or that you want to force into a new naming convention, NameChanger is a free utility that can handle the batch rename job for you. The app supports regular expressions, mismatched files types and formatting changes.Once installed, drag all of the files you want to rename into the left pane of the app, and then give the app the logic you want it to apply to your files. Basic renames are simple, and the app helps you do things like hide file extensions, change case, append or prepend characters and more. From there, you can do sequential renames, conditional renames based on the original file name, and more. Plus, you can preview the changes in the right pane before committing them. How do you do bulk renames on the Mac? Share your favourite tools in the comments.