RenX

RenX is a simple-to-use application that gets integrated into the Windows Explorer shell extension and lets you rename multiple files in bulk by specifying an intuitive set of rules.
It doesn't come packed with complex options or configuration parameters, so it can be handled by all types of users, even those inexperienced with file renaming tools.

Simple installation and shell extension integration

The setup operation is a fast job that requires minimal user intervention. Afterward, RenX can be accessed by opening the right-click menu of any file or selection of multiple files, via the "Extended Rename ..." entry.

Set rules for renaming file names or extensions

It's possible to change either the file names or extensions. You can replace any string of characters with something else, create a numbered sequence, or append a prefix or suffix to the current file name or extension, depending on your preferences.
In addition, you can enable or disable case sensitive mode, as well as ask the application to apply modifications to every instances. Unfortunately, it doesn't integrate an option for previewing file renaming results, so it's not possible to make any adjustments before proceeding with the task. There are no other notable options available here.

Evaluation and conclusion

We haven't come across any stability issues in our tests, thanks to the fact that the software utility didn't hang, crash or prompt error messages. It carried out tasks swiftly and had minimal impact on computer performance, as it needed low CPU and RAM to work properly.
On the other hand, RenX hasn't been updated for a long time, and our tests have concluded that it doesn't work on newer Windows versions, which renders the app useless to the modern user.