openssl s_client -connect example.com:443 -servername example.com 2>/dev/null | openssl x509 -noout -dates

Category: Self-Hosting

openssl s_client -connect example.com:443 -servername example.com 2>/dev/null | openssl x509 -noout -dates

Connect to a live HTTPS server and print the certificate's validity window

Connects to a live HTTPS server and prints its certificate's validity dates. Checks what the server is actually serving, not just what's on disk.
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