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 klaas-boergmann.de

Expired
Issued by (CA)
Let's Encrypt
Subject
api.klaas-boergmann.de
Valid from
Apr 23, 2026
Valid until
Jul 22, 2026 (expired 47 days ago)
Public key
EC 256-bit
Serial
063C7D4CFD52F376B6C08E27B03A47DF78EB
SHA-256 fingerprint
42:88:BB:20:CC:FF:85:4A:5D:12:47:07:4E:97:33:70:EC:46:AD:6C:CC:65:08:22:A2:66:A9:8F:60:BA:B4:41
Chain
E7 → ISRG Root X1
Subject Alternative Names (2)
api.klaas-boergmann.de, app.klaas-boergmann.de

Certificate Authority Authorization (CAA)

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

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TLS certificate

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