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 semestra.ch

Valid
Issued by (CA)
Let's Encrypt
Subject
semestra.ch
Valid from
Jun 4, 2026
Valid until
Sep 2, 2026 (30 days remaining)
Public key
RSA 2048-bit
Serial
06E35084329B5C2386AEC7CB52DA1BFBD428
SHA-256 fingerprint
B7:27:78:04:A1:E8:E0:C5:01:B3:FC:3F:19:B4:50:09:51:F6:E3:1B:BD:91:6C:AA:90:21:6D:2E:5C:DA:86:40
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
semestra.ch, www.semestra.ch

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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