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 m-opitz.ch

Valid
Issued by (CA)
Let's Encrypt
Subject
m-opitz.ch
Valid from
Oct 10, 2026
Valid until
Jan 8, 2027 (80 days remaining)
Public key
EC 256-bit
Serial
05149DDB13E2D03BD08C800DB25630B85C7F
SHA-256 fingerprint
8B:CB:AE:F1:FD:62:7A:63:60:03:C8:D7:1F:F6:B5:46:F8:33:9F:50:3B:D0:56:D2:8D:75:81:F9:79:BF:02:9A
Chain
YE1 → Root YE → ISRG Root X2 → ISRG Root X1
Subject Alternative Names (2)
m-opitz.ch, www.m-opitz.ch

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 12, 2026.

Never get surprised by m-opitz.ch's certificate expiring

This is today's certificate. Turn on monitoring and we'll watch m-opitz.ch continuously, notifying you the moment anything moves across all three signals:

Certificate monitor showing the issuer, expiry date, chain status, fingerprint, covered names, and a history of a rotation and an expiry warning

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, CNAME, TXT 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.