CryptSync: Automated encryption and synchronization between pairs of folders

Automatic sync tasks are a capability offered by many applications, but if you really want to know your backups are safe, give CryptSync a try. This open-source tool will also encrypt and compress data in your backup folder, making it inaccessible for outsiders.

Installation & Requirements

CryptSync’s setup offers no other settings except choosing the install folder’s location. The rest of the install process is fully automated and completes very quickly. CryptSync occupies about 2 MB of hard drive space so this small utility has no requirements other than one of the following 32 or 64-bit operating systems: Windows XP, Vista or 7.


CryptSync’s interface shows a simple list of all folder pairs, offering the possibility to delete any of them or add new ones. The New Pair window requires users to select the two folders: the original one, where the files reside in their plain form, and the encrypted folder, where the same data will be stored in an encrypted form. The folders can be located anywhere on the computer or on another terminal connected to your local network.

To protect the contents of the encrypted folder you’ll have to set up a password. You’ll also have the possibility to scramble the filenames in the encrypted folder. By default, any change made in any of the folders will reflect in the other one. Using the “Mirror original folder to encrypted folder” option will make CryptSync ignore changes made in the encrypted folder, leaving the original one unchanged. This can be very useful since changing the contents of the encrypted folder can cause file redundancy errors. When you add a new file in the encrypted folder, the program will sync the paired folders, copying it in its unencrypted form in the original folder. This would also count as a new modification so CryptSync will process it too. Apparently, modifying encrypted text documents will trigger a correct synchronization.

CryptSync uses 7-Zip for the encryption, which will also compress the encrypted files. By default, the program stored the encrypted data in the .cryptsync file format but users have the option of changing the format to .7z. Also, any files that you want to remain unencrypted can be added into a list.

There are to sync options available on the main window: “Run in background” – this will allow CryptSync to silently monitor any changes made to paired folders, while running in the system tray; “Sync files and exit” – the plain, one-time, manual sync job that will exit the program upon completion.

Besides adding specific files to be ignored from encryption in the “New Pair…” dialog you can also set specific file formats to be skipped from the sync tasks completely in the main window and of course enable CryptSync to start with Windows.

CryptSync can be used to sync two folders located on the same computer or network, and can be especially useful when it complements cloud storage tools such as Dropbox and SkyDrive. The program will encrypt and compress data that you want to store in the cloud, rendering the data unusable if someone were to find out the password to your online storage account.


– Fast and extremely simple installation.
– Users can easily set sync tasks for paired folders, located on the same computer or different computers from the same network.
– The program offers the option to ignore changes made to the encrypted folder.
– For automated sync tasks, CryptSync runs silently in the background.


– Paired folders cannot be edited.
– Users are not alerted when background sync jobs are carried out, and the program doesn’t display the progress status of these jobs.


CryptSync is a convenient, free solution to strengthen the security of any cloud storage service, but it’s undeniably useful even when you’re simply storing the encrypted data on another computer. Moreover, CryptSync carries out automated sync tasks in an unobtrusive manner and it also compresses the encrypted data.