To quickly check multiple sites: openssl s_client -connect <host>:<port> < /dev/null 2>/dev/null | openssl x509 -text -in /dev/stdin | grep "Signature Algo

To quickly check multiple sites: openssl s_client -connect <host>:<port> < /dev/null 2>/dev/null | openssl x509 -text -in /dev/stdin | grep "Signature Algorithm" From http://stackoverflow.com/questions/26473076/how-do-i-check-if-my-ssl-certificate-is-sha1-or-sha2-on-the-commandline http://stackoverflow.com/questions/26473076/how-do-i-check-i...