SSL Certificate Checker

How to Use the SSL Certificate Checker

1. Enter a domain: Type the website domain (e.g., example.com) into the Domain Name input field — no https:// prefix needed.
2. Click "Check SSL": Press the button to query the domain's SSL certificate information.
3. Review validity status: The tool shows whether the SSL certificate is valid (green check) or invalid (red cross).
4. Inspect protocol details: View the TLS protocol version and cipher suite used by the server's certificate.
5. Check HTTP status: The HTTP status code confirms whether the server is responding correctly over HTTPS.

Technical Overview & Use Cases

The SSL Certificate Checker queries a secure API endpoint that establishes a TLS handshake with the target domain and inspects the certificate details returned during the connection negotiation. It verifies certificate validity (whether it's expired, self-signed, or issued by a trusted Certificate Authority), identifies the TLS protocol version (TLS 1.2, TLS 1.3), and reports the cipher suite used for encryption. The tool also checks the HTTP status code to confirm the server responds properly over HTTPS. This is useful for diagnosing mixed-content warnings, expired certificates, or misconfigured TLS settings without needing to use command-line tools like openssl s_client or navigate browser developer tools.

Real-world use cases:

• Certificate Monitoring: Quickly verify that your SSL certificate hasn't expired or been misconfigured after a server update or migration.
• Security Auditing: Check whether a domain uses modern TLS 1.3 or is still on older, less secure protocol versions.
• Pre-launch Verification: Confirm SSL is properly configured before launching a new website or subdomain to avoid browser security warnings.

Privacy & Security Guarantee

This tool is part of the FAK LAB ecosystem, founded by Faizan Ahmad Khan Khichi. The domain name you enter is sent to a secure API that performs a standard TLS handshake with the target server — the same connection any browser would make when visiting that site. No private keys, authentication data, or personal information is transmitted or stored. Results are displayed in your browser and discarded after viewing. No data is ever stored or shared.

Frequently Asked Questions

What does it mean if the SSL status shows "Invalid"?

An invalid status typically means the certificate has expired, is self-signed (not issued by a trusted CA), the domain name doesn't match the certificate's Common Name or Subject Alternative Names, or the certificate chain is incomplete. Contact your hosting provider or certificate issuer to resolve these issues.

Does this tool check certificate expiry dates?

The tool checks overall validity, which includes whether the certificate has expired. If the certificate is expired, it will show as "Invalid." For specific expiry date information, you can inspect the certificate directly in your browser's address bar lock icon.

What TLS protocol version should my site be using?

TLS 1.3 is the current recommended standard, offering improved security and faster handshakes compared to TLS 1.2. While TLS 1.2 is still considered secure, TLS 1.0 and 1.1 are deprecated and should be disabled. If your site reports TLS 1.0 or 1.1, you should update your server configuration immediately to protect your users.