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 on-tek.com

Valid
Issued by (CA)
Let's Encrypt
Subject
on-tek.com
Valid from
Sep 5, 2026
Valid until
Dec 4, 2026 (71 days remaining)
Public key
RSA 2048-bit
Serial
06887A522366DF3659805E4127AADD1DA10B
SHA-256 fingerprint
54:0A:56:58:5E:93:6D:AA:E1:56:CD:F2:27:6C:84:D4:4F:A9:81:A1:7D:31:3B:DD:24:85:E5:6A:97:45:56:F3
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (2)
on-tek.com, www.on-tek.com

Certificate Authority Authorization (CAA)

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

We've observed 1 previous certificate for this host. This certificate has been served since Sep 18, 2026.

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This is today's certificate. Turn on monitoring and we'll watch on-tek.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.

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