Difference between CER and CRT and how to convert them?
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10/18/2020 by admin with 0 comments

Difference between CER and CRT and how to convert them?

I am sure you have heard a lot about the SSL certificates and why they matter most when comes to website security.

If you are a website owner one way or another you are going to need SSL certificates and I can even say that your website performances will affects if you don’t have any SSL certificates installed on them.

SSL certificates are something that gets installed on your website and protects your website from middle man attaches and all other malicious intended attacks.


SSL certificates are X.509 Certificates

X.509 certificates are PKI-based certificates meaning theses certificates work on the public key and private key infrastructure. So SSL is based on PKI infrastructure.

To get SSL certificates you have to make a request to the Certificates Authority about getting one and have to select which types of SSL certificates do you need.

Even though the function of SSL certificates is the same no matter from which Certificates Authority you get your certificates from they can be changed in the file format.

As we all know the certificates Authority have their system through which they issue and maintain these certificates so the certificates come with the different file format and different extension.

Though one important thing is every extension and file format is made for different requirements and made with different criteria’s keep in mind.

But when comes to SSL certificates they come with different file format according to different specificities you are going to need. The formats are CER, CRT, P7S, P7B, P12, PEM, and many more.

In this article, we will gaze over these different file formats especially.CER and.CRT and see how to convert them.

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Difference between CER and CRT format

Fundamentally there is no such difference between CER and CET format. Both formats are used for SSL certificates.

The only difference we can say about them is their extension. Certificates with CER format come with .cer extension and certificates with CRT format comes with .crt extension.

Certificates that come with .cer and .cet extension are encoded in DER format or we can say they encoded with ASCII PEM format.

DER formatted certificates are binary so even if you want to see what exactly written in those certificates you cannot as they are of the form 0s and 1s.

Although you can see what has written in other formatted certificates as they are not I binary form and you can simply see them with notepad or any text viewing software.

Certificates that comes with .cer and .cet extensions are base 64 coded.

The only difference is their extension. SSL with CER format has .cer extension while the ones with CRT format have .crt extension.

Now you must be thinking why this matter, right?

Yes. When comes to functionality it does not matter at all those certificates use the same technique to ensure security.

Although the thing that matters is servers. The different server needs a different type of SSL certificates extension.

If you are thinking but why do I need to convert from .cer to .crt let me explain it with a simple example.

Let say you want some important documents for your exams. So you tell your sister to send those documents via email.

When your sister sent you the email containing documents you download those file which you got through email.

But the problem is a file sent to you is in .doc format and you are required to upload all the documents in .pdf format.

In this case, even though the data is going to be the same in both the format the system’s requirement is different.

Which is why you are required to change the format of your document from .doc to .pdf

Similarly, even though SSL with the .cer and .crt is worked the same and functioned same the web servers on which they are going to upload are different.

Here webservers meaning the servers of your hosting servers and that is why you may be required to convert SSL with .cer to .crt format or it can be .crt to .cer

Now you get an idea about why conversion is needed let’s jump right into how to convert them.

Conversion from.CRT format to.CER

The process is very simple. Just like converting any normal file, we do.

First, locate your Certificate Authority has provided you with.

Search for yourwebsite.crt file and double click on it. A certificate wizard will pop up.

In which select the “Details” option which is in the 2nd position.

After clicking on details you will see some files don’t touch them. Select the copy to file option at the very bottom of the certificate window.

Then press next.

After that, you will see another wizard pop up in which “select Base – 64 encoded X.509 (.CER)

Hit next.

Select Browse in the certificate wizard to search for a destination and type in the filename yourwebsite.

Click on finished.

And at the end hit next.

And you will get the SSL certificate file with .cer extension

Conversion of .CER to .CRT format

Sometimes it may convert .cer into .crt generally with Apache servers.

You can do that with the following command.

$ openssl x509 –inform DER –in ssl_certificate.cer –out ssl_certificate.crt

By just looking at the command you can understand that it is telling OpenSSL to convert your .cer formatted certificate into .crt format.

Well, one thing I forget to mention you have to install OpenSSL in your computer before using this command.

Openssl is free software provide by Apache.


Final Note

Both the .cer and .crt format of SSL certificates are used in java servers.

So before doing anything first check your server and hosting. Because a wrong upload and installation can not only waste your time but also will affect the security of your website.

So if you are unsure about the result try to use Google to search for the error first. Although those conversions from one format to another do not change the functionality of your SSL certificates making it safe to interchange your certificates into each other.


Also Read-

How Secure is 256-bit Encryption?

What is SSL Checker, How to Verify an SSL Certificate?

How to fix ERR_CONNECTION_REFUSED error in chrome




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