Free tool · Security
Inspect certificate expiration, issuer, and other relevant TLS certificate information. Enter an address to see when its certificate expires, who issued it and whether browsers will trust it.
The day after which browsers stop trusting the certificate and show a full-page warning. Renew well before it: two weeks of margin is a common rule.
The issuer is the authority that signed the certificate. The names list shows which domains the certificate covers: your address must be one of them.
A green mark means nothing needs attention. A warning means the certificate works but expires soon. A problem means visitors would see an error right now.
Browsers block the page with a security warning, most visitors leave, and API clients refuse the connection. The site is effectively down until the certificate is renewed.
The check connects from our servers, not from your device. A different result usually means a certificate that is served only to some visitors, a missing intermediate certificate or a recently renewed certificate that is not deployed everywhere yet.
A single check shows the state right now. Certificates expire silently, so continuous monitoring with an alert before the expiry date is what protects you.
UptimeWire runs these checks for you around the clock and alerts you when something changes. Start with the free plan, no card needed.
