Web and TLS Tools
Use web tools when users see browser errors, protocol negotiation issues, or inconsistent headers. This section combines HTTP behavior, certificate analysis, and security posture checks.
When to use this category
- A site loads but behaves inconsistently across clients or regions.
- TLS expiry, chain issues, or ALPN negotiation affects availability.
- Security headers or HTTP/2/HTTP/3 readiness need verification after change windows.
What you get from these pages
- Actionable interpretation for headers, protocol negotiation, and cert state.
- Clear distinction between advertised vs. confirmed HTTP/3 behavior.
- Operational remediation guidance for edge, origin, and CDN teams.
Operator tips
- Validate redirect hops before assuming origin behavior is the root cause.
- Treat certificate renewal automation as a monitored production dependency.
- Re-check protocol and headers after each CDN or load balancer deployment.
Tools in this category
Frequently asked questions
Why do protocol checks matter if pages still load?
Silent protocol regressions often degrade latency, reliability, or compatibility before hard failure.
Should TLS tests run only near certificate expiry?
No. Run routinely to catch chain, SAN, or negotiation drift early.
Can security headers break application features?
Yes. Roll out strict CSP and framing controls with staged validation.
Is Alt-Svc proof of working HTTP/3?
No. Alt-Svc advertisement must be validated with confirmed QUIC connectivity.
What is the best sequence for web diagnostics?
Headers, TLS certificate test, then HTTP/2+HTTP/3 check for protocol posture.