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 der-seminar.de

Valid
Issued by (CA)
Let's Encrypt
Subject
der-seminar.de
Valid from
Jun 23, 2026
Valid until
Sep 21, 2026 (53 days remaining)
Public key
EC 256-bit
Serial
05C5E916F1CED5DAF070D5C18440C09D771E
SHA-256 fingerprint
77:A1:0D:FA:7C:4B:58:84:1B:85:89:42:DB:C8:7F:E6:E6:1C:7C:B5:82:43:51:CB:3B:84:C0:E9:85:C8:C8:AC
Chain
YE2 → Root YE → ISRG Root X2 → ISRG Root X1
Subject Alternative Names (2)
der-seminar.de, www.der-seminar.de

Certificate Authority Authorization (CAA)

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

This certificate has been served since Jul 26, 2026.

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DNS changes

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TLS certificate

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