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 up-down.cz

Valid
Issued by (CA)
Let's Encrypt
Subject
up-down.cz
Valid from
Aug 14, 2026
Valid until
Nov 12, 2026 (66 days remaining)
Public key
RSA 2048-bit
Serial
06B83ED9C0B387B9BBB1886497D715A43732
SHA-256 fingerprint
42:01:83:01:0C:6B:28:75:01:A3:F3:C7:F7:D3:42:1C:0C:4B:E0:39:15:DF:DC:93:08:B8:4A:62:AB:F5:4B:FE
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
*.up-down.cz, up-down.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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