Pemeriksa TLS/SSL
Periksa versi TLS, ALPN, cipher, rantai sertifikat, SAN, dan masa berlaku host apa pun.
Tentang
This TLS checker helps you validate HTTPS configuration for a domain. It’s useful when you see certificate warnings, handshake errors, or need to confirm what protocol/cipher the server negotiates.
You can inspect certificate chain details, subject alternative names (SANs), and expiry dates to plan renewals and avoid downtime. ALPN information can also help confirm HTTP/2 or HTTP/3 negotiation paths depending on server support.
If results look different from your browser, remember that CDNs, geo routing, and SNI/ALPN negotiation can vary. Always test the exact hostname users visit, including www vs non-www.
FAQ
›Why does the browser show a certificate warning?
Common causes include expired certificates, hostname mismatch, or incomplete certificate chains.
›What is a certificate chain?
It’s the sequence of certificates from your leaf certificate up to a trusted root CA.
›What are SANs?
Subject Alternative Names list the hostnames a certificate is valid for (e.g., example.com, www.example.com).
›What is ALPN?
ALPN negotiates the application protocol (like HTTP/2) over TLS during the handshake.
›Does this fix TLS issues?
No. It helps diagnose the configuration so you can adjust server/CDN settings and renew certificates correctly.
Alat Terkait
- HTTP Headers & Redirects/tools/network/headers
- DNS Propagation Checker/tools/network/dns-check
- What Is My IP?/tools/network/my-ip
- ASN / Prefix Lookup/tools/network/asn
- SPF/DKIM/DMARC Checker/tools/network/email-auth