Cyberduck

Cyberduck is a free, open source file transfer and cloud storage browser for macOS and Windows, used by admins and developers to move files over SFTP, FTP and WebDAV and to manage buckets in Amazon S3, Azure, Google Cloud Storage and Backblaze B2 from one window. A Cyberduck download gets you the same program on both desktop platforms, plus an optional command-line client, duck, that also runs on Linux.

It is developed by iterate GmbH and licensed under the GPL. The free build shows an occasional donation prompt; a registration key received after donating removes it. Paid builds are also sold through the Mac App Store and the Microsoft Store for those who prefer store installs.

Cyberduck at a glance

What it does

• Connects to FTP, FTPS, SFTP, WebDAV and SMB servers.
• Browses object storage: Amazon S3 and S3-compatible services, Microsoft Azure, Google Cloud Storage, OpenStack Swift and Backblaze B2.
• Opens consumer and team clouds: Google Drive, Dropbox, OneDrive, SharePoint, Box, Nextcloud, ownCloud, DRACOON and Files.com.
• Edits remote files in your local editor and uploads them again when you save.
• Encrypts data client-side with Cryptomator vaults, including file names.
• Saves connections as bookmarks and keeps a transfer queue you can pause and resume.
• Synchronises a local folder with a remote one.
• Offers the same engine as a scriptable CLI (duck) for jobs and CI pipelines.

How sysadmins use it

Connect to a Linux server over SFTP with a key

1. Click Open Connection and choose SFTP (SSH File Transfer Protocol).
2. Enter the server name, port 22 (or your custom port) and the username.
3. In the SSH Private Key field select your key file, for example ~/.ssh/id_ed25519. Leave the password empty if the key has no passphrase.
4. Connect, then use Bookmark > New Bookmark to save the connection so the team does not retype details.

Inspect and clean up an S3 bucket

1. Open Connection, choose Amazon S3, enter the Access Key ID and Secret Access Key of an IAM user with the minimum rights you need.
2. Browse buckets like folders. Use Get Info on an object to check its size, storage class and metadata.
3. For S3-compatible storage (MinIO, Wasabi and similar), use the matching connection profile or set the provider’s endpoint instead of the default AWS one.

Scripted transfers with duck

The CLI uses URLs for every protocol. Typical commands:

duck --list sftp://admin@web01.example.com/var/www/
duck --upload sftp://admin@web01.example.com/var/www/ ./release.tar.gz --identity ~/.ssh/id_ed25519
duck --download s3:/my-logs-bucket/2026/09/ ./logs/
duck --synchronize sftp://admin@web01.example.com/srv/share/ ./share/

1. Install duck with the package manager of your platform (Homebrew brew install duck, Chocolatey choco install duck, or the official DEB/RPM repositories).
2. Test with --list first, then add --upload or --download.
3. Add --verbose when you need to see the protocol exchange while debugging.

Install and first run

• Windows: Windows 10 64-bit or later. Since 9.5.2 the Windows build runs on .NET 10. The installer puts Cyberduck in the Start menu; saved passwords go to the Windows Credential Manager.
• macOS: macOS 10.13 or later on Intel or Apple silicon. Homebrew users can install it with brew install --cask cyberduck. Passwords are stored in the macOS Keychain.
• Linux: there is no graphical Cyberduck; use the duck CLI.
• Network: SFTP needs outbound TCP 22 (or your custom port). Plain FTP in passive mode needs the server’s passive port range open; prefer SFTP or FTPS where possible.
• Cloud accounts: Google Drive, OneDrive, Dropbox and Box connections sign in through the provider’s OAuth page in your browser, so allow that step on locked-down machines.

Limitations

• No mounted drive: files are browsed in Cyberduck’s window. Mounting remote storage as a drive letter or Finder volume is the job of the separate commercial product Mountain Duck.
• No Linux GUI, only the CLI.
• The free build asks for donations from time to time until you add a registration key.
• Not a sync or backup service: synchronisation runs when you start it, not continuously.
• No built-in SSH terminal; you still need an SSH client for shell work.

Cyberduck vs alternatives

WinSCP is the usual choice on Windows when you live in SFTP and SCP: it has a two-pane commander layout, PuTTY integration and a strong scripting language, but it is Windows-only and has limited cloud support beyond S3. Cyberduck wins when you need macOS and Windows with the same interface, or many cloud providers in one tool. For bulk scripted cloud copies, rclone is another common CLI option. If you need continuous replication between machines instead of transfers, look at Syncthing.

FAQ

Is Cyberduck free?

Yes. The builds from the official website are free and open source under the GPL; donating gets you a registration key that removes the donation prompt. The Mac App Store and Microsoft Store editions are paid.

Is Cyberduck safe?

Cyberduck is an established open source project with public source code on GitHub. Use it over encrypted protocols (SFTP, FTPS, HTTPS-based cloud APIs) and install it only from the official site or a trusted package manager.

Is there Cyberduck for Linux?

Only the command-line client, Cyberduck CLI (duck), which is available as DEB and RPM packages and as a Docker image. The graphical app is macOS and Windows only.

Cyberduck vs FileZilla: which is better?

FileZilla focuses on FTP, FTPS and SFTP with a classic two-pane layout. Cyberduck covers the same protocols plus many cloud storage services and Cryptomator encryption, in a single-pane browser.

How do I connect Cyberduck to S3?

Choose Open Connection, select Amazon S3 and enter your Access Key ID and Secret Access Key. For other S3-compatible providers, use their connection profile or custom endpoint.

How do I save a connection in Cyberduck?

After connecting, use Bookmark > New Bookmark. Bookmarks keep the host, protocol, username and path; passwords are saved in the system keychain or Credential Manager.

Cyberduck vs Mountain Duck: what is the difference?

Both come from iterate GmbH. Cyberduck is the free browser-style client; Mountain Duck is a paid product that mounts the same servers and clouds as drives in Finder or File Explorer.

Last checked against official sources: 30 September 2026 (developer website: cyberduck.io). Versions and licence terms change — confirm on the developer's site before deploying in production.