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 spera-foundation.org

Valid
Issued by (CA)
Let's Encrypt
Subject
spera-foundation.org
Valid from
Jul 10, 2026
Valid until
Oct 8, 2026 (35 days remaining)
Public key
EC 256-bit
Serial
05476F027402CBD7C437813AC58A10201FA8
SHA-256 fingerprint
F4:C8:9E:DB:04:45:FD:C9:57:24:0D:34:3F:AD:08:E1:56:AC:8E:A1:D2:B1:BA:D0:96:42:C8:12:62:00:7D:F7
Chain
YE2 → Root YE → ISRG Root X2 → ISRG Root X1
Subject Alternative Names (2)
spera-foundation.org, www.spera-foundation.org

Certificate Authority Authorization (CAA)

No CAA policy is published for this domain — any certificate authority may issue for it.

This certificate has been served since Sep 2, 2026.

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Uptime

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DNS changes

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TLS certificate

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