Cyberduck is an open-source client for FTP and SFTP, WebDAV, and cloud storage (OpenStack Swift, Amazon S3, Backblaze B2 and Microsoft Azure), available for macOS and Windows (as of version 4.0) licensed under the GPL. Cyberduck is written in Java and C# using the Cocoa user interface framework on macOS and Windows Forms on Windows. It supports FTP/TLS (FTP secured over SSL/TLS), using AUTH TLS as well as directory synchronization. The user interacts with the user interface (GUI), including file transfer by drag and drop and notifications via Growl. It is also able to open some files in external text editors. Cyberduck includes a bookmark manager and supports Apple's Keychain and Bonjour networking. It supports multiple languages including English, Catalan, Czech, Chinese (Traditional and Simplified), Danish, Dutch, Finnish, French, German, Hebrew, Hungarian, Indonesian, Italian, Japanese, Korean, Norwegian, Polish, Portuguese, Russian, Slovak, Spanish, Swedish, Thai, Turkish, Ukrainian, and Welsh. Cyberduck CLI The Cyberduck creator also provides a version for the command-line interface (CLI), called duck, available for Windows, macOS and Linux. It has its own website at duck.sh. The program can be used as FTP and SFTP-client, for operations with different cloud services. See also Comparison of FTP client software References External links Portable Cyberduck — packaged as portable application for external drive. (Mac only) Free FTP clients SSH File Transfer Protocol clients MacOS Internet software Data synchronization MacOS-only free software Cloud storage