SSL / HTTPS Availability Checker
Verify a site serves HTTPS successfully and view certificate availability and protocol signals.
About This Tool & Technical Logic
The checker confirms that a domain responds over HTTPS and reports what the connection reveals. Browsers deliberately hide raw certificate details from web pages, so a full field-level certificate reader requires a server-side check — this tool verifies reachability and validity signals from the client side.
A successful HTTPS fetch guarantees the certificate chain validated (browsers refuse otherwise): dates are current and the chain is trusted. Failures distinguish DNS errors from TLS errors, which pinpoints whether the problem is DNS or the certificate.
HTTPS request via relay — success implies a browser-valid certificate chain; error classes map to failure causes.
How to Use — Step by Step
- 1
Enter the domain or URL
The https:// scheme is applied automatically if omitted.
- 2
Read the verdict
Green = HTTPS live and chain-valid. A TLS error with working DNS means certificate expiry/misconfiguration; a DNS error is a different problem entirely.
- 3
Act on the failure class
Expired/mismatched cert: renew or fix SANs. Mixed content: fix internal http:// links — browsers block them on secure pages.
Frequently Asked Questions
Not from a browser page — raw certificate fields are inaccessible to JavaScript. The pass/fail result reflects exactly what browsers enforce, which is often what you need.