SSL/TLS Certificate Lookup

Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted

SSL/TLS Certificate for petnik.cz

Expiring soon
Issued by (CA)
Let's Encrypt
Subject
petnik.cz
Valid from
Jul 27, 2026
Valid until
Oct 25, 2026 (20 days remaining)
Public key
RSA 2048-bit
Serial
068A89D51747DB9559EB624089877C48ED99
SHA-256 fingerprint
2F:7C:A2:AD:9C:8C:AD:B9:F5:C3:C1:65:81:15:4F:59:78:88:F1:0D:CD:7D:FE:4F:23:6E:10:FA:0E:A7:FF:88
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
*.petnik.cz, petnik.cz

Certificate Authority Authorization (CAA)

No CAA policy is published for this domain — any certificate authority may issue for it.

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Uptime

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DNS changes

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TLS certificate

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