A simple X.509 certificate viewer for Microsoft Windows.


In order to display an X.509 certificate, simply drop a certificate file onto the CertViewer window. Alternatively, you can copy a certificate to the clipboard – by default, CertViewer continuously monitors the clipboard for “displayable” certificates. Last, but not least, it is possible to pass certificates to CertViewer via the command-line.

CertViewer currently supports certificates in the binary (DER) and the Base64-encoded (PEM) format, as well as key-stores in the PKCS #12 (PFX) and the JKS (Java KeyStore) format, including password-protected files.


The .NET Framework 4.7.2 or later is required!

It is already included in Windows 10 v1803 (April 2018 Update) or later, and all versions of Windows 11.

Program settings

The initial program settings can be adjusted in the CertViewer.exe.config configuration file.

All settings are specified in the /configuration/appSettings section:


For news and updates, please check the official project website at:

Git mirrors:

Contact information


OpenPGP key:
F81B 9C6C 6C3A 7F46 4173 3F5E E9C6 473D 4E97 DAD1


Copyright (c) 2024 “dEajL3kA” <Cumpoing79@web.de>
This work has been released under the MIT license. See LICENSE.txt for details!


CertViewer includes the following works: