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 plain-act.com

Valid
Issued by (CA)
Let's Encrypt
Subject
plain-act.com
Valid from
Sep 3, 2026
Valid until
Dec 2, 2026 (59 days remaining)
Public key
RSA 2048-bit
Serial
050B0F701CA6D2BC955B639907FB032C3469
SHA-256 fingerprint
8F:D5:0C:B1:99:8F:46:2E:17:2E:AD:74:6F:17:AE:0D:FD:B7:07:02:CC:CE:08:49:F6:90:31:60:36:95:A5:9F
Chain
YR1 → Root YR → ISRG Root X1
Subject Alternative Names (1)
plain-act.com

Certificate Authority Authorization (CAA)

The serving CA (Let's Encrypt) is authorized by this domain's CAA records (letsencrypt.org, pki.goog, sectigo.com).

Never get surprised by plain-act.com's certificate expiring

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