Before diving into the conversion process, it’s important to understand the difference between PEM and CER certificate formats. PEM stands for Privacy Enhanced Mail, and it is a base64 encoded format that is commonly used for X.509 certificates, Certificate Signing Requests (CSRs), and private keys. CER, on the other hand, is a binary format that is used for X.509 certificates.
Why Convert a PEM Certificate to a CER Certificate?
There are several reasons why you might need to convert a PEM certificate to a CER certificate. One common reason is if you need to import the certificate into a Windows system that only supports the CER format. Another reason might be if you need to use the certificate with a Java-based application that only supports the CER format.
One key takeaway from this text is that converting a PEM certificate to a CER certificate can be necessary in certain situations such as when you need to import the certificate into a Windows system or use it with a Java-based application that only supports the CER format. You can easily convert a PEM certificate to a CER certificate using the OpenSSL command-line tool and verify the conversion by checking the details of the CER certificate to ensure they match the original PEM certificate.
Using OpenSSL
To convert a PEM certificate to a CER certificate, you can use the OpenSSL command-line tool. Here’s how:
Open a command prompt or terminal window.
Navigate to the directory where your PEM certificate is located.
Run the following command:
openssl x509 -outform der -in certificate.pem -out certificate.cer
Replace “certificate.pem” with the name of your PEM certificate, and “certificate.cer” with the name you want to give your CER certificate.
Press enter.
Your PEM certificate will now be converted to a CER certificate and saved in the same directory.
A key takeaway from this text is that understanding certificate formats is important before converting from one format to another. The conversion from PEM to CER certificate can be done using OpenSSL command-line tool. The reasons for conversion include the need to import the certificate into a Windows system or the use of the certificate with a Java-based application. To verify the successful conversion, use the OpenSSL command that displays the details of the CER certificate.
Verifying the Conversion
To verify that the conversion was successful, you can use the following command:
openssl x509 -in certificate.cer -inform der -text -noout
This command will display the details of your CER certificate. If the details match those of your original PEM certificate, then the conversion was successful.
FAQs – Convert Certificate from PEM to CER
What is a PEM certificate?
PEM (Privacy Enhanced Mail) is a base64 encoded X.509 digital certificate format used for secure communication over the internet. PEM certificates contain the private key, public key, and the certificate details in a single file.
What is a CER certificate?
CER (X.509 Certificate) is a binary format that contains only the certificate details, and not the private or public key. CER certificates are widely used in Microsoft Windows environments.
Why convert from PEM to CER?
There may be situations where you need to use a certificate in a CER format, such as performing SSL/TLS encryption in a Microsoft Windows environment. In such cases, you will need to convert the PEM certificate to a CER certificate format.
How can I convert a PEM certificate to a CER certificate?
You can convert a PEM certificate to a CER certificate using several methods. One of the easiest ways is to use OpenSSL, an open source command-line tool used for encrypting, decrypting, and converting files. The command to convert a PEM certificate to a CER certificate is as follows:
openssl x509 -in certificate.pem -out certificate.cer –outform der
Are there any other methods for converting a PEM certificate to a CER certificate?
Yes, you can use other tools such as the Windows Certificate Manager and the OpenSSL GUI tool. However, these methods may not be as straightforward as using the OpenSSL command line tool. It is recommended that you research more about each method before using them.
Are there any risks associated with converting a PEM certificate to a CER certificate?
There is no risk per se, as the conversion process only involves changing the format of the certificate file from PEM to CER. However, it is always recommended to perform a backup of your original certificate file before attempting any conversion.
Can I convert a CER certificate to a PEM certificate?
Yes, you can convert a CER certificate to a PEM certificate using OpenSSL. The command to convert a CER certificate to a PEM certificate is as follows:
openssl x509 -inform der -in certificate.cer -out certificate.pem
Can I use a CER certificate in a Linux environment?
Yes, you can use CER certificates in a Linux environment. However, it is important to note that Linux typically uses PEM certificates instead of CER certificates. If you need to use the certificate in a Linux environment, you will need to convert the CER certificate to a PEM certificate.