SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
one-x.co.jp
SSL/TLS Certificate
SSL/TLS Certificate for one-x.co.jp
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- www.one-x.co.jp
- Valid from
- Oct 28, 2026
- Valid until
- Jan 26, 2027 (72 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 05029F2FFF201323FCB037EECBDF18870420
- SHA-256 fingerprint
- AE:1B:71:63:00:A3:A5:69:E5:99:D0:78:30:8C:61:91:51:24:6F:69:34:81:BD:06:8A:45:83:B2:67:A5:F9:D9
- 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.
We've observed 2 previous certificates for this host. This certificate has been served since Oct 29, 2026.
Never get surprised by one-x.co.jp's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch one-x.co.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, CNAME, TXT 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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