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 optocom.com

Valid
Issued by (CA)
Sectigo Limited
Subject
www.optocom.com
Valid from
Feb 16, 2026
Valid until
Mar 19, 2027 (240 days remaining)
Public key
RSA 2048-bit
Serial
5D01659D61F112292037B19FE7286407
SHA-256 fingerprint
16:BC:BC:92:B3:FC:3D:E0:F1:9B:7B:3F:38:45:7E:1C:B9:FA:6C:AC:BF:61:18:94:90:63:21:21:48:2B:FB:BD
Chain
Sectigo Public Server Authentication CA DV R36 → Sectigo Public Server Authentication Root R46 → USERTrust RSA Certification Authority
Subject Alternative Names (2)
optocom.com, www.optocom.com

Certificate Authority Authorization (CAA)

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

Never get surprised by optocom.com's certificate expiring

This is today's certificate. Turn on monitoring and we'll watch optocom.com 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.