SSL Certificate Scanner
Complete a real TLS handshake against any host and read back the certificate, the chain, the negotiated cipher, and a graded security score.
Running it here is free and never spends credits — the page calls the same production endpoint your integration would.
Everything the endpoint returns
The playground above shows the same fields the API responds with — nothing is held back for the paid tier.
Certificate details
Subject, issuer, serial number, SHA-256 fingerprint, and every Subject Alternative Name on the cert.
Full chain
Leaf to root, each certificate in order, so a missing intermediate is obvious at a glance.
Expiry window
Exact valid-from and valid-to timestamps, plus the number of days left before renewal is due.
Security grade
A 0–100 score and letter grade derived from TLS version, cipher suite, and chain completeness.
Validation checks
Common-name match, SAN coverage, CA trust, and whether the certificate is self-signed.
Connection facts
The negotiated TLS version and cipher suite, the same values openssl s_client would report.
Three steps, no signup
Enter a domain
A bare hostname or a full URL both work — example.com and https://example.com resolve to the same scan.
We open a real TLS session
The scanner completes a handshake against port 443 and reads the certificate the server actually presents.
Read the report
Grade, chain, and validation checks land together. Copy any fingerprint or serial straight from the result.
Built for
Web developers
Verify SSL configuration and troubleshoot certificate issues during a deployment.
DevOps engineers
Watch expiry dates and validate compliance across staging and production.
System administrators
Audit server configuration and confirm the chain is served in the right order.
Security teams
Assess posture and catch weak ciphers or untrusted issuers before an audit does.
Site owners
Catch an expiring certificate before it takes the site down.
Frequently asked
Ready to run this on a schedule?
The same endpoint, called from your code, billed in credits.