SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
seibo-y.ed.jp
SSL/TLS Certificate
SSL/TLS Certificate for seibo-y.ed.jp
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- seibo-y.ed.jp
- Valid from
- Sep 21, 2026
- Valid until
- Dec 20, 2026 (81 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 0526D51ABF5456F24D32DB0C5927DDDCC123
- SHA-256 fingerprint
- 86:45:04:F7:4C:E8:5C:61:8E:4B:42:4A:C2:47:81:C1:98:4F:43:1A:3E:D7:96:39:EE:80:C7:60:A1:20:2D:CD
- 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 28, 2026.
Never get surprised by seibo-y.ed.jp's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch seibo-y.ed.jp continuously, notifying you the moment anything moves across all three signals:
Uptime
We visit the site from multiple regions worldwide and email you within minutes if it goes down, with a per-region breakdown so a real outage stands out from a regional blip.
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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