SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
friis-andersen.nu
SSL/TLS Certificate
SSL/TLS Certificate for friis-andersen.nu
Hostname mismatch- Issued by (CA)
- Let's Encrypt
- Subject
- mail.s-mart.dk
- Valid from
- Sep 9, 2026
- Valid until
- Dec 8, 2026 (22 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 067962D70626DBA556CC57207B95C4E15AD1
- SHA-256 fingerprint
- 2B:C6:00:B6:25:25:49:ED:A4:F2:96:EC:4B:AA:23:95:D4:A3:5A:75:18:B2:BE:9F:BC:CE:53:6A:98:2C:CA:B0
- 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.
Never get surprised by friis-andersen.nu's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch friis-andersen.nu 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.
Free for your first domain: uptime, DNS, and certificate together. No credit card.