What SSL Checker does
SSL Checker resolves the hostname to a public address, pins one resolved endpoint, connects on port 443 with SNI, and reads the certificate and TLS session details returned to the PagesTools server. It calculates validNow from certificate authorization plus the not-before and not-after dates.
The result is a point-in-time view from one network location and one selected address. Large sites may serve different certificates by region or endpoint. The tool does not perform a complete protocol matrix, cipher-suite scan, OCSP or CRL audit, HSTS review, certificate transparency search, mixed-content check, or browser compatibility test.
How to use SSL Checker
- Enter a public HTTPS hostname without a path; a URL is also normalized to its host.
- Select Inspect certificate to resolve an address and connect on port 443.
- Review authorization, validNow, days remaining, subject, issuer, alternative names, protocol, cipher, and fingerprint.
- Investigate failures with the certificate provider and test other endpoints or client paths when the service is distributed.
Important details
Authorization and date validity both matter
validNow becomes true only when the TLS library authorizes the certificate and the current server time falls between validFrom and validTo. The authorization error is shown when the chain or hostname cannot be accepted.
One public address is selected
The tool prefers a public IPv4 address when available and otherwise uses the first public resolved address. Other addresses behind the same hostname may present different configurations.
Days remaining is calendar guidance
The value is calculated from the certificate's not-after timestamp and current server time, rounded up to days. It does not know whether automated renewal is configured or will succeed.
Practical uses
- Check the currently served certificate after an HTTPS deployment.
- Review remaining validity while investigating a renewal alert.
- Compare subject alternative names and issuer details during hostname troubleshooting.
Privacy and limitations
The hostname is sent to PagesTools, which performs DNS resolution and a TLS connection from its server. The destination can log that connection; the returned certificate report uses no-store cache headers.
The check covers one address and one TLS connection on port 443 from the PagesTools location. It is not a comprehensive SSL Labs-style scan and does not verify every endpoint, protocol, cipher, revocation path, HSTS rule, or client environment.