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 cm-castromarim.pt

Valid
Issued by (CA)
Let's Encrypt
Subject
cm-castromarim.pt
Valid from
Jul 3, 2026
Valid until
Oct 1, 2026 (61 days remaining)
Public key
RSA 4096-bit
Serial
05066DBD586439316B1A9CA968A2D40A8D48
SHA-256 fingerprint
3E:15:FC:12:40:F4:09:89:23:04:1F:A0:E0:EA:12:6E:56:3D:41:82:9F:1F:C9:47:DE:A7:DA:A3:BF:82:A3:13
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (8)
100memorias.cm-castromarim.pt, biblioteca.cm-castromarim.pt, cm-castromarim.pt, diasmedievais.cm-castromarim.pt, novbaesuris.cm-castromarim.pt, www.biblioteca.cm-castromarim.pt, www.cm-castromarim.pt, www.diasmedievais.cm-castromarim.pt

Certificate Authority Authorization (CAA)

The serving CA (Let's Encrypt) is authorized by this domain's CAA records (comodoca.com, globalsign.com, letsencrypt.org, sectigo.com).

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TLS certificate

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