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 ext.com

Valid
Issued by (CA)
Google Trust Services
Subject
ext.com
Valid from
Jul 25, 2026
Valid until
Oct 23, 2026 (42 days remaining)
Public key
EC 256-bit
Serial
837BB9A19C914FE41364C7166073DF4B
SHA-256 fingerprint
34:5F:37:BB:D8:49:DA:8B:57:AF:16:32:08:33:25:83:9D:86:9D:00:C3:91:55:58:D4:4F:BA:B5:2B:F9:F6:41
Chain
WE1 → GTS Root R4
Subject Alternative Names (2)
*.ext.com, ext.com

Certificate Authority Authorization (CAA)

The serving CA (Google Trust Services) is authorized by this domain's CAA records (comodoca.com, digicert.com, letsencrypt.org, pki.goog, ssl.com, trust-provider.com).

Never get surprised by ext.com's certificate expiring

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