Cyberduck Mountain Duck CLI

Cryptomator Transparent, client-side encryption support in Cyberduck and Mountain Duck to secure your data on any server or cloud storage. Based on the excellent concepts and work of Cryptomator. Encryption for data at rest prevents unauthorized access regardless of the server or cloud storage infrastructure. Version 6


The Cryptomator security architecture in Cyberduck and Mountain Duck has many crucial advantages over other client-side encryption solutions.

Secure and Trustworthy with Open Source
Open source software that can be audited independently for security. You can rest assured there are no backdoors and no hidden vulnerabilities. No online service subscription or account required. You will always have access to your data without the risk of a service shutting down.

Filename Encryption
File and directory names are encrypted, directory structures are obfuscated.

File Content Encryption
Unlike disk encryption utilities, each file is encrypted for its own.

Open Documentation

Client-side Encryption Comparison


Version 6.0 Version 6

Mountain Duck

Version 2.0 Version 2


Version 2.11


Version 1.9.1

Interoperable with Cryptomator

Open Source


No account required

Client side encryption of file contents

Client side encryption of filenames


Obfuscation of directory tree

No known security flaws

Browse remote files

Access files in Finder (macOS) or Explorer (Windows)

Provider and protocol independent implementation

Installation requires no adminstrator privilege