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 f-standard.co.jp

Valid
Issued by (CA)
Let's Encrypt
Subject
www.f-standard.co.jp
Valid from
Jul 7, 2026
Valid until
Oct 5, 2026 (47 days remaining)
Public key
RSA 2048-bit
Serial
05F1064E2E34DCCB4268505FB8E1B30E53F8
SHA-256 fingerprint
2B:0C:F3:CA:62:A9:50:74:DE:10:FB:AE:47:0B:5B:83:16:2C:8A:74:C2:32:C6:CD:34:11:86:DA:49:B6:96:93
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
f-standard.co.jp, www.f-standard.co.jp

Certificate Authority Authorization (CAA)

No CAA policy is published for this domain — any certificate authority may issue for it.

Never get surprised by f-standard.co.jp's certificate expiring

This is today's certificate. Turn on monitoring and we'll watch f-standard.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, 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.

Monitor this certificate free

Free for your first domain: uptime, DNS, and certificate together. No credit card.