Cryptographic TLS Inspection

SSL/TLS Certificate Checker

Inspect any domain’s live HTTPS certificate: expiration countdown, issuing CA, covered SAN hostnames, negotiated TLS protocol, and trust chain integrity.

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Frequently Asked Questions

SSL Certificates & TLS Encryption FAQ

What does this SSL/TLS certificate checker inspect?
It establishes a live secure socket connection to port 443 of the target server to inspect certificate authenticity, issuing Certificate Authority (CA), exact expiration date, remaining validity days, Subject Alternative Names (SANs), signature algorithm, and negotiated TLS version.
Why is it dangerous for an SSL certificate to expire?
When a certificate expires, browsers immediately block visitors with full-screen security warnings ("Your connection is not private"). This halts ecommerce transactions, destroys user trust, and triggers severe search ranking drops.
What are Subject Alternative Names (SANs)?
SANs are an X.509 certificate extension allowing a single certificate to secure multiple domains or subdomains (such as medel.es, www.medel.es, or wildcard *.medel.es).
What is the difference between TLS 1.2 and TLS 1.3?
TLS 1.3 is the latest cryptographic protocol. It cuts handshake latency in half via 1-RTT or 0-RTT key exchanges and deprecates legacy, vulnerable cipher algorithms (such as RC4, CBC, or SHA-1), maximizing speed and security.
How can I audit my company’s cryptographic infrastructure?
Our team assesses ciphers, client compatibility, auto-renewal mechanisms, and compliance (PCI-DSS, ISO 27001). You can request a cybersecurity audit to safeguard your communications.