SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
pfaeffli.one
SSL/TLS Certificate
SSL/TLS Certificate for pfaeffli.one
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- pfaeffli.one
- Valid from
- May 29, 2026
- Valid until
- Aug 27, 2026 (36 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 0512B6AD0A5427C525707FE6D5AD9D49573C
- SHA-256 fingerprint
- 8B:99:24:E8:55:94:57:16:4A:F5:4C:AE:70:A8:03:36:49:4A:37:CC:DF:74:B0:D2:23:FE:62:9B:E7:15:4F:D0
- Chain
- YR2 → Root YR → ISRG Root X1
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
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
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