AbstractBrain Answers About us →

How to see a certificate expiration with OpenSSL


How can I see a certificate expiration with OpenSSL?

I have an SSL/TLS certificate and I would like to see when it expires.

Is there any way to see the expiration from command line (e.g. OpenSSL)?


You can use this command to display the certificate expiration:

$ openssl x509 -enddate -noout -in cert.pem

In case the certificate is stored in a format different from PEM, you first need to convert it. For example you can convert .cer to .pem with this command:

$ openssl x509 -inform der -in cert.cer -out cert.pem