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 sembl.io
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- sembl.io
- Valid from
- Sep 23, 2026
- Valid until
- Dec 22, 2026 (82 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 06DCBFA809AE80865A78A5314F451DD3A4F7
- SHA-256 fingerprint
- 55:DF:41:F3:D7:A8:38:6F:96:0A:D7:5C:ED:65:3D:3C:DC:67:8B:F2:1E:15:D9:44:89:D4:0F:EA:B0:9F:74:7C
- Chain
- YR1 → Root YR → ISRG Root X1
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 29, 2026.
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Uptime
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DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
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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