While on the other side, Linux OS has the only command-line version that could be accessible using SSH commands. PuTTYgen.exe is the graphical tool on Windows OS. Although originally written for Microsoft Windows operating system, it is now officially available for multiple operating systems including macOS, Linux. It is one of the components of the open-source networking client PuTTY. PuTTYkey is a key generator tool for creating pairs of public and private SSH keys.