SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
one-mail.jp
SSL/TLS Certificate
SSL/TLS Certificate for one-mail.jp
Valid- Issued by (CA)
- Nijimo, Inc.
- Subject
- www.one-mail.jp
- Valid from
- Jul 29, 2026
- Valid until
- Feb 12, 2027 (196 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 02165962CC033D1F7F8CE262420F49F7
- SHA-256 fingerprint
- 5B:BF:78:A5:C8:33:94:8E:6E:50:61:37:5A:F9:29:89:55:E8:39:1A:EE:44:21:B3:4A:5B:AA:A0:98:DB:EB:58
- Chain
- FujiSSL RSA Domain Validation Secure Server CA 2 → Sectigo Public Server Authentication Root R46 → USERTrust RSA Certification Authority
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
Never get surprised by one-mail.jp's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch one-mail.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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