How to convert CER to PFX | SSL Certificates

We recently had to deploy a wildcard SSL certificate to an Microsoft Azure web app.

The company we buy our certs from, issues them in .crt format by default, we have to convert them to .pfx ourselves. This isn’t a big deal and we’re going to see how to do this today.

Make sure you have the following two or three files depending on your issuer.

  • A certificate file (necessary)
  • A private key file (necessary)

Now that you have the two or three files, login to a shell terminal on your system. You need to make sure you have Openssl installed. This usually comes pre-installed on many systems but it’s still a good idea to check to see if it’s installed:

[email protected]:/root/tmp$ sudo apt-get install openssl

Reading package lists... Done
Building dependency tree
Reading state information... Done
openssl is already the newest version (1.1.1f-1ubuntu2).
openssl set to manually installed.
0 upgraded, 0 newly installed, 0 to remove and 77 not upgraded.

Copy the files into one location and issue the following command to start the conversion:

openssl pkcs12 -export -out clients.abc.com.pfx -inkey clients_abc_com_key.txt -in clients_abc_com.crt

You will be prompted create a password for the pfx certificate file, keep this secure as you’ll need it when you want to install the file.

That’s it, you’re done!