SSL Certificate Checker
Enter a domain to connect to it over TLS the same way a browser does. The check verifies the full certificate chain and hostname, reads the issuer and validity dates, and confirms that plain HTTP requests are redirected to HTTPS.
Results open in the site's full report, which you can share, compare and re-run.
What it checks
- Chain of trust and hostname match (not just the date)
- Issuer and exact expiry date, with days remaining
- HTTP to HTTPS redirect
- HSTS header, which stops downgrade attacks
Frequently asked questions
- Why does a certificate show as invalid when it has not expired?
- Validity also requires a trusted chain and a name that matches the domain. Self-signed certificates, missing intermediate certificates and certificates issued for a different hostname all fail even when the dates are fine.
- How early should I renew?
- Automated issuers such as Let's Encrypt renew 30 days before expiry. Nalyzed flags certificates with fewer than 14 days left, and verified owners can get a webhook alert.
- Is the check free?
- Yes. The result is part of a full, shareable website report.
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