Free Tool
TLS Checker
Check whether your website uses modern HTTPS, valid certificates, safe TLS versions, and reliable redirect behavior.
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What this tool checks
This page uses ZeriFlow's deterministic website security engine and focuses the guidance on the configuration area above. For the full report, run a complete free security scan.
Key Checks
Certificate Validity
Checks whether the certificate is trusted, valid for the hostname, and not expired.
TLS Version Support
Flags outdated protocol support and encourages TLS 1.2 or TLS 1.3 for modern clients.
HTTPS Redirects
Reviews whether HTTP traffic is redirected to HTTPS cleanly without loops or weak temporary redirects.
HSTS Enforcement
Checks whether browsers are instructed to keep using HTTPS after the first secure visit.
Recommended Baseline
Protocols
Support TLS 1.2 and TLS 1.3; disable SSL, TLS 1.0, and TLS 1.1.
Certificates
Use trusted certificates and renew them automatically before expiry.
Redirects
Redirect all HTTP traffic to HTTPS with a permanent redirect.
HSTS
Add a carefully tested Strict-Transport-Security policy.
FAQ
Is TLS the same as SSL?
TLS is the modern protocol used for HTTPS. SSL is the older name many people still use, but production sites should support modern TLS versions rather than legacy SSL protocols.
Which TLS versions should my website support?
Modern websites should support TLS 1.2 and TLS 1.3. TLS 1.0 and TLS 1.1 are deprecated and should be disabled.
Why does certificate expiration matter?
Expired certificates trigger browser warnings that block or discourage visitors. Production certificates should be monitored and renewed automatically before expiration.
Does this replace a full SSL lab report?
No. This page focuses on practical website checks inside ZeriFlow. For deep cipher-by-cipher TLS research, a dedicated TLS lab can still be useful.
Need the full security picture?
ZeriFlow combines deterministic website checks across headers, TLS, DNS, cookies, and email security with monitoring, reporting, and AI-powered developer workflows where implemented.