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 act-center.de

Valid
Issued by (CA)
Let's Encrypt
Subject
act-center.de
Valid from
Aug 22, 2026
Valid until
Nov 20, 2026 (56 days remaining)
Public key
RSA 4096-bit
Serial
06BB2734B0FC63DF340A448787B674D2E791
SHA-256 fingerprint
AD:9D:49:47:25:96:DE:59:69:42:B0:83:A5:95:7E:A9:2C:2E:BB:9B:30:66:04:83:19:F6:CE:60:42:BF:AD:15
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
act-center.de, www.act-center.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

We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.

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