The idCAT Certificate consists of two elements: the public key and the private key. The private key is the element that contains the specific information of the citizen holding each idCAT Certificate, while the public key includes the generic information relating to the characteristics of the idCAT Certificate.
To use the idCAT Certificate for authentication, signature, etc., it is necessary to have the complete idCAT Certificate (public key+private key). However, on some occasions the public key of the idCAT Certificate may be needed, for example to check its validity .
Warning: Never share the private key of your idCAT Certificate . Yes, you can share the public key, for example to resolve an incident in the use of the certificate.
Below we explain how to obtain the public key of the idCAT Certificate, depending on the browser you have it installed on:
Step 1: Go to the button 
from the upper right. Option " Settings ">Privacy and Security>Security- Manage certificates .
Step 2 : select the certificate with your name and issued by EC-Ciutadania and click the "Export" button.
Step 3 : Select the " Do not export private key " option
Step 4: Finally set the file location and name. You already have the public key of the exported idCAT Certificate.
step 1 Go to Key Access > Login > my certificates.
step 2 Select the certificate we want to export, we will see that it shows us that it has a private key.
step 3 Click the right mouse button on the private key of the certificate, a window will open with several options, we must select "Export".
step 4 A window will open where we must select the "certificate (.cer)" file format in the drop-down list, indicate the name of the public key and in which location we want to save it. Finally we will click on Save.
We will now have the public key (.cer) of the idCAT Certificate in the defined location.
Step 1: With the Microsoft Edge browser go to the button from the top right>Settings>Privacy, search and services tab>Security. At this point click on the "Manage Certificates" button and then the " Personal " tab.
Step 2: select the certificate with your name and issued by EC-Ciutadania and click the "Export" button.
Step 3 : Select the " Do not export private key " option
Step 4: Finally set the file location and name. You already have the public key of the exported idCAT Certificate.
Step 1 : Go to Tools >Settings>Privacy and Security > Show certificates
Step 2 : select the certificate with your name and issued by EC-Ciutadania and click the "View" button.
Step 3 : in the "Others" section, press the "PEM(cert)" option
This option will allow you to download the public key of your idCAT Certificate in .pem format.
Step 4 : To change the format to .cer, you can rename the file (by right-clicking on the file and selecting the Rename option) and change the .pem extension to . sky
when you do "intro" the file will already be in the .cer format
You already have the public key of the exported idCAT Certificate.