Validate HTTPS certificates and expiry. Check chain and hostname. Free online SSL checker.
The SSL Certificate Checker validates the TLS certificate for any domain. It shows issuer, validity period, chain, and common issues like expiry or hostname mismatch. Developers use it to verify production certs, debug "not secure" warnings, and plan renewals. Run from our server to avoid CORS when checking third-party domains.
Browsers block cross-origin requests to arbitrary HTTPS endpoints. Our server performs the check so you can test any domain.
Typically issuer, subject, validity dates, SANs, and the certificate chain. Some tools also show key size and signature algorithm.
The tool will show the expiry date and warn. Renew with your CA and install the new cert on your server.
Yes. A valid chain from your cert to a trusted root CA is required for browsers to trust the connection.
Most checkers use port 443 (HTTPS). For custom ports you may need a different tool or CLI.