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 uni-bonn.de

Valid
Issued by (CA)
Let's Encrypt
Subject
uni-bonn.de
Valid from
Jul 12, 2026
Valid until
Oct 10, 2026 (78 days remaining)
Public key
EC 384-bit
Serial
05D0954E7F484174941B81484B78A5930862
SHA-256 fingerprint
D2:95:61:37:00:A2:50:EA:68:4A:12:C8:3A:F3:37:21:25:B9:D6:B5:01:A9:18:28:DC:8F:EF:42:B2:AE:FD:42
Chain
YE1 → Root YE → ISRG Root X2 → ISRG Root X1
Subject Alternative Names (1)
uni-bonn.de

Certificate Authority Authorization (CAA)

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

Never get surprised by uni-bonn.de's certificate expiring

This is today's certificate. Turn on monitoring and we'll watch uni-bonn.de 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.