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 kern.ruhr

Valid
Issued by (CA)
Let's Encrypt
Subject
kern.ruhr
Valid from
May 25, 2026
Valid until
Aug 23, 2026 (27 days remaining)
Public key
RSA 2048-bit
Serial
05FD9F5FC4936CEE0D03417DBF2543FEEBE1
SHA-256 fingerprint
8A:C0:44:21:9B:A1:17:0A:D8:1A:C5:FC:E5:B0:FF:F2:87:66:3F:D5:56:D7:0A:41:08:3A:C9:AF:A7:A8:0E:80
Chain
R13 → ISRG Root X1
Subject Alternative Names (2)
kern.ruhr, www.kern.ruhr

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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