File Synchronization 4+

Nemesys Software, LLC

    • 3.1 • 35 Ratings
    • $7.99



***NOTE: please contact us with any problem. We have been supporting this application for 15 years. We can work with you to resolve any problem.


The real true bidirectional synchronization tool! Many other synchronization apps here use the Unix tool rsync to do their job but they can't offer bidirectional sync. Ask them before buying, you'll see!

File Synchronization synchronizes multiple pairs of folders or files. It has been designed to be easy to use: choose 2 folders to synchronize then click the Synchronize button and you're done! However, there are multiple options when your needs get a little more complicated. The interface is easy to use and the application is quick to do any synchronization that you might need.

3 different synchronization modes to use depending on what you want to achieve:
• Automatic mode: whenever the content of one of the folder you synchronize changes, the synchronization is performed so you can be sure that the 2 folders are always synchronized. You set it once and then forget about it
• Repeat mode: the synchronization is performed at a regular interval that you set in the preferences. Good when you're constantly making changes and don't want the folders to be continuously synchronized
• Manual mode: whenever you want to perform the synchronization, you select the pair in the list and click Synchronize. Ideal if you synchronize a folder that is on a remote volume that might not always be available

2 different synchronization directions:
• Bidirectional: changes in both folders that are synchronized are duplicated in both folders. Best when changes can occur in each folder that you synchronize
• Unidirectional: changes that occur in one of the folder you synchronize are duplicated in the other folder. If you want to have an exact backup of a folder, that's the synchronization mode to use. You can choose to backup the folder on the left or on the right

Preview window:
• See how many items are going to be copied and deleted and what the sizes of those items to copy and delete are
• Check what is going to happen if the synchronization is performed
• Decide which item is going to replace the other
• Remove some items from the list from being synchronized
• Delete items you don't want to be synchronized

Synchronization options for each pair:
• Select the synchronization mode
• Choose the synchronization direction of that pair
• Set filters to ignore certain items
• Decide what happens with orphaned files and recently modified files
• Ignore warnings when both copies of the same file have been modified since the last synchronization
• Include or not invisible items
• See the status of the last synchronization session and when it was last synchronized

Multiple sources for the synchronization:
• Local disks
• Remote volumes shared by another Mac on your network or by a Windows computer
• USB flash drive
• Store login information for remote volumes so that they can be automatically mounted the next time they are needed
• Any volume you can access in the Finder can be used

Additional information:
• Can generate a log each time a synchronization is performed
• Error reporting gives you a description of an error so you can fix it
• Hierarchical views show you exactly where an item is in any list. Double-click an item and it will be selected in the Finder

Note: if you have an issue with the new version, please contact us instead of stating that you're not pleased. We strive to make everybody happy with their purchase but we can't help if you complain here without ever contacting us! Some people obviously post comments while they're missing some important features. Let us help you. You won't have any help by posting comments here.

What’s New

Version 1.6.6

• Include executable binary for Apple silicon
• Fixes the app becoming non-responsive when browsing a large number of files in the Preview window
• Other minor fixes

Ratings and Reviews

3.1 out of 5
35 Ratings

35 Ratings

bananaworks ,

a know bug

UPDATE - 25 january 2013:

the problem below may have been fixed, but now it seems to be scanning a folder that I didn't select to sync on the target drive.

a few months ago, the developer told me they were aware of the problem but have yet to resolve it.

program seems to run fine, but when I try and back-up my mac user files (docs, pictures, etc…), it reports that it it actually copying my old backup to my newer user file - essentially erasing my current files with the older back-ups.

I've been assured that this is a bug they are aware of, but it's troublesome to see your files seemingly being erased. so I've been using get back-up 2 until this gets resolved.

hopefully this will motivate a revised version as this is the best designed back-up software I;ve seen (since silverkeeper has given up)

funes el memorioso ,

Not useful if you add files to one folder

This application purports full bi-directional sync, but it is hobbled by the fact that this is only true with files that have been recently modified. If you happen to add a file to one folder that has not been modified since the last sync, then that file will simply be deleted by the program as an "orphan" without so much as a dialog box or warning message. (Even when the warning message is enabled in the preferences menu.) If you're planning on syncing files one way, the program works well. And if you're planning on just trying to keep two sets of the same files in sync between folders, without ever adding new files to one of those folders, then it will also work for you. But this is not what I understood when I read about a true bi-directional sync. I found another program on the app store that offers a free version and an upgrade to pro at the same cost as this one. It achieves the true bi-driectional sync, includes a saved folder for deleted files in case something goes wrong, and runs in the tray much more inconspicuously than this one--a behavior I prefer. The other may have problems that I'm not yet aware of but, of the two, it's far closer to what I was looking for.

czubad ,

A Full-featured Sync Solution

Other reviewers notwithstanding, it needs emphasis that most users just want an App that works to relieve their lives of mundane repeated procedures. Nemesys developer Laurent Daudelin delivers a fine tool for syncing files across platforms. I’ve used several other file synchronization products on Mac and PC hardware with exceedingly poor results (Unix is an exception, with built-in script tools if you know how to use them). I needed a good tool to sync a 16GB flash drive between my Mac at home and my Windows 7 PC at work. As an educator who teaches up to four different classes at a time, you can imagine my need to keep test, presentation, and grading files in sync. Also, I never know which classroom I may be in, and so idiosynchracies between PCs could be problematic. But File Synchronization works without a hitch. It's robust, conceptually easy for first-time users to understand, and great quality for the money. Buying this software was a good investment.

App Privacy

The developer, Nemesys Software, LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More


  • Family Sharing

    Up to six family members can use this app with Family Sharing enabled.

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