FoldersSynchronizer is a nifty and popular utility for macOS (Apple Silicon and Intel) which synchronizes and backs-up files, folders and disks. You can choose one or more pairs of files, folders or disks then FS will synchronize or backup those exactly.

FS lets you organize your sync and backup on several sessions you can save to a file for a later reuse. On each session you can apply special options like Timers, Multiple pairs of folders, Filters, Exclude Items, Auto-Mount local and remote volumes, launch your own AppleScripts, set how to resolve Conflicts, execute an incremental or an exact copy, include locked files...

FS can display a preview panel listing all the files FS is going to copy, replace and delete. FS can save a log file or send it to a custom email address, and it can sync and automatically quit the application… FoldersSynchronizer has been successfully tested on macOS 14 Sonoma. Look at the previous versions for previous macOSs, for Intel and PPC machines.
Backup
When backing up, the destination folder will be upgraded with the newest files, the new files (new entries) and the new Folders (new entries) coming from the source folder. The source folder will be left untouched. FoldersSynchronizer can execute incremental or exact backups. The incremental backup (default) never deletes items. The exact backup deletes from the destination folder, all the items no longer existing in the source folder, and it never deletes items from the source folder.

Synchronization
When synchronizing, the old files will be replaced with the newest files in both directions. The new files (new entries) will be copied in both directions, as well as new Folders. The old Folders will not be replaced entirely by the newer ones, but their content will be updated with the most recent files, the new files (new entries) and new Folders (new entries). FoldersSynchronizer can execute incremental or exact synchronizations. The incremental synchronization (default) never deletes items from the folders. The exact synchronization deletes from a folder, all the items no longer existing in the mirror folder.

Settings

FS lets you perform a backup or a sync, incrementally or exactly, include the invisible files, resolve the aliases...

Timers

FS can automatically execute Synchronizations and Backup at the date/time and interval you like.

Multiple

FS lets you define up to 32 pairs of folders, disks or files to backup or sync in one shot.

Filters

FS can automatically filter the files and folders from the copy, by file name, file size, creation date...

Exclude

FS lets you exclude files and folders from the copy by dragging these items on the exclude list...

Conflicts

You can specify how to perform in case of various conflicts or decide later how to do that manually.

Mount Volumes

FS can automatically mount and unmount your local and remote volumes, disk images, iDisk...

AppleScript

FS can run your own AppleScript before and after executing each session to perform your tasks.