NebulaSSH vs PuTTY
PuTTY has been the default Windows SSH client for more than twenty years. It is free, tiny, and it works. NebulaSSH solves a different problem: getting a terminal, a file manager and a remote desktop on whatever machine you happen to be sitting at, without installing anything.
PuTTY is a desktop terminal emulator you install per machine. Saved sessions live in the Windows registry on that computer, so a laptop rebuild, a second desktop or a colleague's machine means setting everything up again. NebulaSSH keeps saved sessions in your account, so which machine you are sitting at stops mattering.
File transfer is the clearest split. PuTTY ships PSFTP and pscp as separate command-line tools, and graphical transfers usually mean pairing it with WinSCP. NebulaSSH puts the SFTP file manager beside the terminal in the same tab, so you can drag a folder from your desktop straight onto a remote path without breaking your session.
Reaching the machine is the other split. Both tools connect outbound to a reachable SSH port. NebulaSSH additionally offers a connector agent you install on the target machine, which dials out to NebulaSSH — so a box behind NAT, on a home connection or behind a firewall with nothing forwarded is still reachable.
Keys work differently too. PuTTY uses its own .ppk format generated by PuTTYgen. NebulaSSH takes standard OpenSSH keys, so if you are moving across, export your key to OpenSSH format from PuTTYgen first.
Side by side
| Capability | NebulaSSH | PuTTY |
|---|---|---|
| Install required | None — runs in the browser | An executable on every Windows machine |
| Platforms | Any modern browser: Windows, macOS, Linux, ChromeOS, tablets | Windows first; unofficial ports elsewhere |
| Graphical SFTP | Built in, beside the terminal | Separate PSFTP and pscp tools, or pair with WinSCP |
| Saved sessions | In your account, reachable from any device | Windows registry on that one machine |
| VNC remote desktop | Included from the Professional plan | Not part of PuTTY |
| Machines behind NAT | Connector agent dials out — no port forwarding | Needs a reachable port, a jump host or a VPN |
| Serial, telnet and rlogin | Not supported | Supported |
| Key format | Standard OpenSSH keys | PuTTY .ppk via PuTTYgen |
| Cost | Free tier, paid plans for teams | Free and open source |
When PuTTY is the better choice
No tool wins everywhere. Stay with PuTTY if any of these describe you:
- You want one tiny offline executable, no account, and nothing between you and the host.
- You need a serial console, telnet or rlogin — PuTTY speaks all three and NebulaSSH does not.
- You are scripting with plink or pscp inside existing Windows batch jobs.
- Policy in your organisation rules out reaching infrastructure through a browser.
Common questions
Is NebulaSSH a drop-in replacement for PuTTY?
For SSH sessions, yes — you get a full terminal with multi-tab sessions, saved connections and key authentication. PuTTY also speaks serial, telnet and rlogin, which NebulaSSH does not, so keep PuTTY around if you use those.
Can I use my existing PuTTY key?
Convert it first. NebulaSSH uses standard OpenSSH keys, so open the .ppk in PuTTYgen and use Conversions to export an OpenSSH key, then add that to NebulaSSH.
Do I still need WinSCP alongside it?
No. The SFTP file manager is part of NebulaSSH and sits next to the terminal, with drag-and-drop uploads and whole-folder transfers.
Does it work on a machine where I cannot install software?
Yes — that is the main reason people move. NebulaSSH needs nothing but a browser, so a locked-down work laptop, a shared machine or a Chromebook all work.
Try it on a machine you are sitting at
Open a browser, sign in, add a server. Nothing to install — and nothing left behind if the machine is not yours.