SSL certificate checker
Check a public host’s TLS certificate issuer, dates, covered names and certificate chain status.
Public internet targets only · 10 lookups per minute · Results cached for 10 minutes
Lookup result
This link reruns the lookup; results may change over time.
How to read the results
The issuer signs the certificate. Validity dates define its lifetime; negative days left means it has expired. Covered names must match the host. A valid chain means the host certificate passed this server’s trust checks, including hostname matching. This is a point-in-time TLS check on port 443, not a complete security audit.
Frequently asked questions
What does an invalid chain mean?
Possible causes include an untrusted issuer, an expired certificate, a missing intermediate certificate or a hostname mismatch. Check the returned chain error.
Does a valid certificate guarantee a safe website?
No. A valid certificate supports encrypted communication and host authentication. It does not establish that website content is trustworthy.
Lookups run from our server. We don't store your lookups. Our web server keeps standard access logs, including IP addresses, for security. Rate limits use temporary hashed identifiers in memory; no database is used.