$ openssl s_client -connect example.com:443 < /dev/null 2> /dev/null | openssl x509 -text | grep Not Not Before: Sep 25 09:14:02 2014 GMT Not After : Oct 27 09:49:54 2017 GMT Register as a new user and use Qiita more conveniently You get articles that match your needsYou can efficiently read back useful informationYou can use dark themeWhat you can do with signing up