SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
marum-alumni.de
SSL/TLS Certificate
SSL/TLS Certificate for marum-alumni.de
Hostname mismatch- Issued by (CA)
- Let's Encrypt
- Subject
- groupware.marum-alumni.de
- Valid from
- Oct 12, 2026
- Valid until
- Jan 10, 2027 (69 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 068CC960318B057344B7F2C7F5E2499F5719
- SHA-256 fingerprint
- 31:A7:E1:FE:26:BB:D6:AD:18:8E:44:D4:4D:D8:25:84:1E:C2:53:58:01:C2:9C:2A:C9:F9:3E:03:22:17:2B:A1
- Chain
- YR2 → Root YR → ISRG Root X1
Certificate Authority Authorization (CAA)
The serving CA (Let's Encrypt) is authorized by this domain's CAA records (letsencrypt.org, pki.dfn.de).
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Uptime
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DNS changes
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TLS certificate
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