OCSP checker
Looks up the certificate's OCSP responder and asks it whether the certificate has been revoked.
What is OCSP checker?
OCSP (Online Certificate Status Protocol) is how a browser checks in real time whether a certificate has been revoked before its expiry date — a compromised or mis-issued certificate gets revoked, and OCSP is what catches that.
How to use it
Enter a hostname; the tool finds its OCSP responder and, where the server allows shell access to OpenSSL, asks it directly whether the certificate is good, revoked, or unknown.
Example
A valid, non-revoked certificate reports: Certificate status: Good