SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
tojaku-h.ed.jp
SSL/TLS Certificate
SSL/TLS Certificate for tojaku-h.ed.jp
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- tojaku-h.ed.jp
- Valid from
- Jun 20, 2026
- Valid until
- Sep 18, 2026 (51 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 05485143E89366C97F4DA230257F5BD18A23
- SHA-256 fingerprint
- 5F:6A:9C:0F:DE:AE:1E:97:18:B6:B2:13:08:77:CC:67:B1:A0:D1:C0:18:10:62:FC:CB:BC:9F:C5:D9:9D:AE:89
- Chain
- YR2 → Root YR → ISRG Root X1
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
Never get surprised by tojaku-h.ed.jp's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch tojaku-h.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.
Free for your first domain: uptime, DNS, and certificate together. No credit card.