SSL certificate checker
Connect to a public site on port 443 and read the certificate it presents, including the name, issuer, and expiration.
This one uses a server lookup because the job cannot finish on the device alone.
How to use it
- 1Enter a public hostname or an HTTPS URL.
- 2Read whether the name matches and whether the trust check passed.
- 3Check the expiration date and the days remaining.
- 4Copy the result if you need to keep it. Kiln does not store the lookup.
When it helps
- See when a public certificate expires.
- Check that the presented name matches the site.
- Tell an expired certificate apart from a connection failure.
Good to know
- The check is one connection to port 443. It is not a vulnerability scan and it does not grade the server configuration.
- Trust uses this server's normal certificate verification. Verification is not turned off to read a failed certificate.
- A private, loopback, or reserved address is refused before a connection is opened.
- The hostname is sent to Kiln for that one connection. The certificate is not stored.
Questions
Does a trusted result mean the website is safe?
No. It means the certificate presented on port 443 matched the hostname and passed the trust check at the time of the connection.
Why is an expired certificate still shown?
When the handshake presents a certificate and then fails verification, Kiln reports the dates and the reason. A connection that fails before any certificate arrives has no certificate fields.
Related tools
HTTP header checker HTTP header checker
Show the status and response headers for one public URL. Redirects are not followed.
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DNS lookup DNS lookup
Look up public DNS records for a domain. Kiln does not connect to the host.
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