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 bez-seka.pl

Hostname mismatch
Issued by (CA)
Let's Encrypt
Subject
opensite.pl
Valid from
Jun 21, 2026
Valid until
Sep 19, 2026 (58 days remaining)
Public key
EC 384-bit
Serial
05F6B22543509E31D7C3F8207B153568363D
SHA-256 fingerprint
CA:3E:E1:C1:C5:A8:5F:FC:6E:85:D5:48:06:E9:11:9E:D1:F1:93:4E:D8:44:B1:A2:C8:6A:BD:BC:CE:B1:9E:C6
Chain
YE1 → Root YE → ISRG Root X2
Subject Alternative Names (3)
opensite.pl, serv1a.opensite.pl, www.opensite.pl

Certificate Authority Authorization (CAA)

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

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TLS certificate

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