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 o-s-a.si
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- o-s-a.si
- Valid from
- Jul 15, 2026
- Valid until
- Oct 13, 2026 (58 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 057869BACD29B76CD440A18DD1ABD1213FFE
- SHA-256 fingerprint
- 02:B6:25:46:7D:41:2C:BA:70:AE:28:D1:6E:AB:5D:C9:F3:07:C5:6E:D7:F4:50:35:DD:D9:F4:5F:0C:AC:51:8E
- 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.
This certificate has been served since Aug 10, 2026.
Never get surprised by o-s-a.si's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch o-s-a.si 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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