SSL Certificate Checker

Read and analyze the TLS certificate a server presents.

Hostname

Connects to port 443 and reads the TLS certificate presented by the server.

What Is a SSL Certificate Checker?

The SSL Certificate Checker connects to a hostname on port 443, reads the TLS certificate it presents, and displays details including the issuer, validity dates, key type, signature algorithm, serial number, fingerprint, subject alternative names, and the full trust chain. It also indicates whether the certificate is currently within its validity window and whether the chain is trusted by the system.

How to Use This SSL Certificate Checker

1
Enter a hostnameType a domain such as example.com (no protocol needed).
2
Click CheckThe tool performs a TLS handshake and extracts the certificate.
3
Review the reportInspect validity, issuer, SANs, and the certificate chain.

Frequently Asked Questions

Yes. The tool opens a real TLS connection on port 443 to fetch the certificate presented by the server. It uses a short timeout and strict SSRF protection.

It may mean the certificate is self-signed, expired, or not signed by a certificate authority the system recognizes. This can be normal for internal or testing servers.

Only the requested hostname is used to establish the connection. No other data is transmitted.

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