OpenSSH and PuTTY keys are of different formats and will have to be converted to each other's format if you want to use the same key between the 2 programs.
OpenSSH private key can be converted to PuTTY's ppk (PuTTY Private Key) format using PuTTYgen.
Download
PuTTY Key Generator (
puttygen.exe) from the official website and launch the program.

https://www.chiark.greenend.org.uk/~sgtatham/putty/latest.html
Click on the
Load button.

Set the
Files of type to
All Files (*.*), select your
SSH's private key file and click on the
Open button.

Enter your key's passphrase if prompted and click on the
OK button.

A prompt will pop up once conversion is successful and click the
OK button.

Edit any key parameters if necessary and click on
Save private key.

Select the location and filename to save the generated key to and click on the
Save button.

Author:
Mohd Shakir Zakaria Cloud architect by profession but always consider himself as a developer, entrepreneur and an opensource enthusiast.
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