FreeFileSync

FreeFileSync is an open source solution for comparing and syncing the directories within your Mac computer.

This program might come in handy when making local backups for your important files and keep the data in sync.

It supports drag-and-drop actions, immediately completes any given task, and uses minimum CPU resources while comparing and syncing folders.

Simply import the two directories you wish to compare and/or sync and click the "Compare" button. Then, check which files are missing from which folder. If the directories aren't synced, use the program's synchronizing feature. The utility will quickly finish the sync task.

The only thing missing from this tool is an integrated help manual which might prove to be of good use to people who are new to this type of Mac programs.

In conclusion, I'd say it's worth giving FreeFileSync a try. The tool works 100%, enables you to save sync profiles for later, and provides you with accurate statistics based on the program's usage for comparing and syncing directories. In addition, unlike many of its competitors, this utility comes without a price tag.