SSL Certificate Checker
Check a domain's SSL/TLS certificate: issuer, validity dates and days remaining.
Frequently asked questions
Why can't my browser do this itself?
Your browser only shows you certificate details for pages you're actively visiting, it can't be scripted to check an arbitrary domain from a web page. This tool connects to the target server directly from a backend function instead.
What does "not trusted" mean?
It means the certificate is expired, self-signed, or issued by a certificate authority that isn't in the standard trusted list, visitors would likely see a browser warning.
Does this check the whole certificate chain?
It reports the leaf certificate presented by the server and whether Node's trust store considers it valid, similar to what a browser checks, though not as exhaustive as a full SSL Labs-style deep scan.