iFreeSftp

iFreeSftp is a free, open-source SFTP client for Windows built on WinUI 3. Each of the two file panes has its own independent tabs - local or remote, in any mix - so you can work across several servers at once without opening a dozen windows.

Its distinguishing feature is an optional server-side command channel on top of SFTP. When the server allows it, a same-host remote-to-remote copy runs as a single cp command on the server, instead of being downloaded to your PC and uploaded again; deleting a large directory tree is one rm -rf rather than thousands of round trips. Checksums (SHA-256, SHA-512, SM3) are computed on the server too, so verifying a multi-gigabyte file is instant.

It also supports remote editing with automatic upload-back, folder comparison, synchronization, active keep-alive, and ships as a self-contained single executable with no installer and no runtime dependency. When the command channel is unavailable it falls back to plain SFTP, so worst case it behaves like any other SFTP client.