How to use a PuttyGen private key to connect to a OpenSSH server

A quick reminder in case I ever forget: If you need to generate a new public/private key on a Windows box your best bet is PuttyGen. The Problem is that PuttyGen will create a SSH2 key that you can't use in your authorized_keys file as OpenSSH is using a different key format.

Thankfully ssh-keygen supports converting keys from one format into another:

ssh-keygen -i -f my_putty_key > ssh2_compatible_key.pub

Then just upload the file to your server and append it to your authorized_keys:

cat key.pub >> ~/.ssh/authorized_keys