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 u-f-o.sk
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- u-f-o.sk
- Valid from
- Jun 28, 2026
- Valid until
- Sep 26, 2026 (65 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 05DD59188236A2FBCAA328B82CF7B7DF7549
- SHA-256 fingerprint
- FA:CB:A2:2A:20:8E:6E:13:2B:2B:81:E1:E4:76:81:E0:C0:2F:71:53:0C:E7:C2:49:36:E9:AD:FA:79:4B:CC:47
- 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 u-f-o.sk's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch u-f-o.sk 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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