SSL/TLS Check
Inspect a website's SSL certificate, expiration, TLS protocol and connection details.
What is an SSL/TLS certificate check?
An SSL/TLS check inspects the certificate and encrypted connection presented by a public website or hostname. It can reveal certificate issuer, validity dates, subject names, Subject Alternative Names, negotiated TLS protocol and cipher information.
TLS certificates help browsers authenticate servers and establish encrypted connections. A valid certificate does not guarantee that a website is trustworthy, but certificate and protocol problems can prevent secure connections or trigger browser warnings.
How to check SSL and TLS
- Enter the public hostname you want to inspect.
- Run the SSL/TLS check.
- Review certificate validity, issuer, SANs, TLS protocol, cipher and resolved IP addresses.
Understanding SSL/TLS results
The certificate validity period shows when the certificate becomes valid and when it expires. Subject Alternative Names indicate which hostnames the certificate is intended to cover.
The negotiated TLS protocol and cipher describe the encrypted connection established during the current test. Server configuration can change over time, and different clients may negotiate different supported protocols or ciphers.
Common uses for SSL/TLS checks
- Check whether a certificate is expired or nearing expiration.
- Verify that a hostname appears in the certificate SAN list.
- Identify the certificate issuer.
- Inspect the negotiated TLS version and cipher.
- Troubleshoot browser certificate or HTTPS connection errors.