SSL/TLS Certificate Lookup

Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted

cosum.in-berlin.de

SSL/TLS Certificate

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SSL/TLS Certificate for cosum.in-berlin.de

Valid
Issued by (CA)
Let's Encrypt
Subject
cosum.de
Valid from
Sep 28, 2026
Valid until
Dec 27, 2026 (42 days remaining)
Public key
RSA 2048-bit
Serial
065CC2B771E3E9678F5C1E53AAD24DA55215
SHA-256 fingerprint
9E:E0:87:D8:28:10:B1:3D:39:D3:4E:63:25:10:17:58:30:B6:D9:7D:71:A2:E7:9A:79:7C:04:00:D3:C4:7D:60
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (12)
berlin.cosum.de, brb.cosum.de, cosum.de, cosum.in-berlin.de, demo.cosum.de, h4f.cosum.de, im-aufbau.cosum.de, nrw.cosum.de, preview.cosum.de, rlp.cosum.de, test.cosum.de, www.cosum.de

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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