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 symbios.sk

Valid
Issued by (CA)
Let's Encrypt
Subject
symbios.sk
Valid from
Nov 4, 2026
Valid until
Feb 2, 2027 (87 days remaining)
Public key
RSA 2048-bit
Serial
06F08CE61CF0A5801FD047C451ED0F839473
SHA-256 fingerprint
DF:4B:CB:B3:91:8A:19:97:CF:C8:F5:80:77:36:5A:FE:00:34:1D:E2:39:00:99:61:48:FF:EF:85:8A:D2:C5:6E
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (3)
mail.symbios.sk, symbios.sk, www.symbios.sk

Certificate Authority Authorization (CAA)

The serving CA (Let's Encrypt) is authorized by this domain's CAA records (letsencrypt.org, sectigo.com).

We've observed 1 previous certificate for this host. This certificate has been served since Sep 23, 2026.

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TLS certificate

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