SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
it-sec.cz
SSL/TLS Certificate
SSL/TLS Certificate for it-sec.cz
Self-signed- Issued by (CA)
- Let's Encrypt
- Subject
- judospartapraha.dev-null.cz
- Valid from
- Sep 1, 2026
- Valid until
- Nov 30, 2026 (76 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 06585DA5680CEDAFBC090AD3BD301E1634EB
- SHA-256 fingerprint
- B6:51:2D:B3:68:6D:A8:6C:D4:41:08:E2:DB:AE:90:D9:39:C1:B5:55:C9:59:D1:38:8B:F8:CE:5D:A5:00:B7:18
- Chain
- YR2 → Root YR
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
Never get surprised by it-sec.cz's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch it-sec.cz continuously, notifying you the moment anything moves across all three signals:
Uptime
We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.
DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
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