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-klempner.de

Valid
Issued by (CA)
Let's Encrypt
Subject
der-klempner.de
Valid from
Jun 19, 2026
Valid until
Sep 17, 2026 (55 days remaining)
Public key
RSA 2048-bit
Serial
05D7E6B1077BA79140E276E533BC361CDC57
SHA-256 fingerprint
9C:6A:B3:A3:16:BC:28:BF:3A:BC:F1:DE:2D:12:AA:4D:A4:A6:7B:08:A6:91:06:A4:36:3B:25:4A:97:AD:38:20
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
der-klempner.de, www.der-klempner.de

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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