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 gpup.com.tw

Valid
Issued by (CA)
Let's Encrypt
Subject
*.gpup.com.tw
Valid from
May 26, 2026
Valid until
Aug 24, 2026 (31 days remaining)
Public key
RSA 2048-bit
Serial
06EABED6C0A2F43151114C6F2471DFD80D1A
SHA-256 fingerprint
F7:FF:86:B8:70:15:5C:BD:9A:BE:78:C3:50:64:5C:19:88:A0:1B:68:F5:E7:CB:5B:5F:65:1D:27:9C:0D:60:B8
Chain
R13 → ISRG Root X1
Subject Alternative Names (3)
*.gp.gpup.com.tw, *.gpup.com.tw, gpup.com.tw

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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