SSL Certificate
Inspect a site's TLS certificate: issuer, validity, SANs and expiry.
Frequently asked questions
What does the SSL certificate checker show?
The certificate's common name and subject alternative names, the issuer, the validity dates and days remaining, the signature algorithm, and the chain of intermediate certificates.
How do I know if a certificate is about to expire?
The tool shows the exact expiry date and the number of days left, and warns when a certificate has expired or expires within two weeks.
Can I check a certificate on a non-standard port?
Yes. Enter the host and set the port field — for example 8443 or 993 — and the tool reads the certificate presented on that port.