How to convert PEM file to PPK using PuttyGen

When using keys for SSH (Secure Shell) connections, different programs often need different formats. Two common key formats are PEM (Privacy Enhanced Mail) and PPK (PuTTY Private Key). PuTTY, an SSH client, uses the PPK format, but sometimes you might get a PEM format key. So, you need to convert PEM to PPK.

In this article, we’ll show you a detailed, step-by-step guide on how to convert PEM to PPK using a free tool called PuttyGen.

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PEM to PPK conversion (quick instructions)

Here is the quick instructions to convert PEM file to PPK using puttygen.

1. Download and install PuTTYgen on your system.
2. Open PuTTYgen application.
3. Click on “Load” and select your PEM file.
4. Click on “Save private key” and choose the PPK format.
5. Save the file.

PEM to PPK conversion (detailed instructions)

PuttyGen is a key generator tool for creating pairs of public and private SSH keys. It is part of the PuTTY suite, though it can also be downloaded independently.

1. You can download it from the official PuTTY website. Once downloaded, run the installer and follow the on-screen instructions to install it on your system.
2. Double-click on the downloaded PuttyGen file to launch the application. You’ll see the key generation interface. For our current task, we won’t generate a new key but instead convert an existing one.

   

3. In the PuttyGen interface, click on the ‘Load’ button in the right-side panel. Navigate to the location of your PEM file, select it, and click ‘Open’. If you don’t see your PEM file, ensure the file type dropdown is set to ‘All Files (*.*)’.

   

4. In case, puttygen shows error message “Couldn’t load private key (not a private key).” Don’t worry, this just means that we need to tell PuttyGen that this is an RSA key.

   Go back to the main PuttyGen window and navigate to ‘Conversions’ from the top menu. Click on ‘Import key’. Navigate back to your PEM file, select it, and click ‘Open’.

5. At this point, your PEM key will be loaded successfully into PuttyGen.

   

6. Back on the main PuttyGen window, click on the ‘Save private key’ button. A warning will pop up asking if you want to save this key without a passphrase. For simplicity, click ‘Yes’. However, in real-world use, it’s a good idea to secure your key with a passphrase. In the file explorer window, go to where you want to save your PPK file, give it a name, and click ‘Save’.

And that’s it! You’ve successfully converted a PEM file to a PPK file using PuttyGen. You can now use this PPK key file to log in to your SSH sessions with PuTTY or any other SSH client that supports PPK.

Conclusion

Working with different SSH key formats might seem complicated at first, but tools like PuttyGen make it much easier. By following these steps, you can easily convert your PEM keys to PPK, making sure they’re compatible with your SSH client. Always remember to handle your keys carefully, as they provide access to your secure servers and services.