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How to extract an SSL certificate from a website in Chrome

This is a quick post about extracting SSL certificates from websites, we'll need this step for some of the future posts that I'm going to write about SSL and HTTPS stuff.

In general, you may want to extract this whenever you are trying to use some tool (not a web browser) or a code to access this website. Then after extracting this, you will require to install this into your tool or framework. With this post, I'm just covering the extraction part.

I'll use the Chrome browser since it is one of the common browsers that is being used.


In my example, I'm going to extract the public certificate of https://letsencrypt.org/. (Let's Encrypt is one of the free Certificate Authority, probably I'll discuss this in one of the future posts.)


1. First, go to the website using the Chrome web browser.

The website has to be in HTTPS. Otherwise, we don't want to do this in the first place. So, make sure your URL is starting with https://...

2. Click on the padlock icon of the browser on the left in the URL and select the Certificate from the menu as below.




Then you will see the certificate dialog box as below.


In the General tab, you can see some of the basic information about this certificate. Who issued this, when it was certified (valid from) and when it expires (to) and to whom it was issued.


3. Go to the Details tab


4. Click on the Copy to File


5. Click Next in the Certificate Export Wizard, then you will see the below screen to select the certificate export options.

Note: Why we selected that is because most of the tools support this format. For example, if you want to add this into the Java Trust store, it would be ideal and it supports Java keytool as well. However, the selection depends on what you are going to do with the certificate.


6. Select Base-64 encoded X.509 (.CER) and hit Next


7. Provide the file path to export. The name can be anything, just to represent the website, I have used the website name.

8. If you click next, it will show a message that it successfully exported.

If you open up the extracted certificate using a text editor, it will look like below.


If it looks like that, then you have successfully extracted the public certificate of the website you wanted.



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