Boxcryptor Alternative

Boxcryptor has been acquired by Dropbox and will terminate free accounts as of January 31, 2023. Till then, all users have to look for an alternative. It is not clear how customers with existing contracts are served in the future and no new accounts are accepted. So why not use Mountain Duck with support for the Cryptomator vault format independent from a single provider?

Smart Synchronization

Mountain Duck allows you to mount multiple cloud storages and servers as network drives on macOS and Windows using Smart Synchronization for offline access. Use the built-in, fully interoperable support for Cryptomator vaults to encrypt your sensitive data in password-protected vaults with end-to-end and zero-knowledge encryption. You do not need to have the Cryptomator apps installed but can access the same vault using Cryptomator for iOS for example.


Cryptomator is free and open-source software with no security by obscurity, no hidden backdoors from third parties, no need to trust anyone except yourself. No online services, no subscriptions, no accounts.


Follow these steps to migrate documents currently in Boxcryptor to a Cryptomator vault accessible through Mountain Duck:


Follow our documentation for step-by-step instructions to create a new vault or access an existing vault stored on your preferred cloud storage (including Dropbox).

Local Cache Size Limitation

Mountain Duck 4.12 introduces new settings to allow cache management — a top requested feature.

In Smart Synchronization connect mode all files you work with (e.g. open, save, upload or explicitly choose to keep offline) are saved in the local cache to shorten access times and to make them editable when offline. Depending on the size of your files, this might eat up your local disk space. This can be problematic in particular for computers with a small SSD disk. The new cache management feature gives you the ability to define a retention time for files and to limit the size of the cache in general. Both settings can be enabled either separately or in combination.

The first option defines the retention time in days after which a file is purged from the cache when it was not accessed during this period. The size option is a soft limit that does apply on a bookmark basis and excludes files marked to be kept offline by the user. In any case, older files are always purged first.

View and Retrieve Previous File Versions

Cyberduck 8.4 and Mountain Duck 4.12 revamp support to view and retrieve previous versions. Instead of the context menu, previous versions are now listed into the Versions tab of the Info window.

Using the buttons in the lower-left corner, you can perform different actions on the selected version:

  • Revert to this version
  • Delete the version permanently
  • View the version using QuickLook on macOS or open this version in the default editor application on Windows.

The versioning feature is now available for Amazon S3, Backblaze B2, Dropbox, Google Drive, Google Cloud Storage, Microsoft OneDrive, and Microsoft Sharepoint connections. You can find full interoperability information in the documentation available.

Connection Profiles

Cyberduck 8 and Mountain Duck 4.8 introduce a new Profiles preferences tab that allows to install additional connection profiles on demand. This makes it much easier to connect to various hosting and cloud storage service providers without the need to lookup connection details other than credentials.


You can either scroll through the list of profiles or use the Search function. To install a connection profile simply enable the corresponding checkbox. The profile will be downloaded and saved in the “Profiles” folder of the application support directory right away. Since Mountain Duck and Cyberduck refer to the same application support directory the connection profiles are shared between both applications. Disabling the checkbox deactivates the connection profile for the currently used application.


Service providers that define connection profiles and open an issue to request the connection profile to be added to the default repository.