SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
1-city.de
SSL/TLS Certificate
SSL/TLS Certificate for 1-city.de
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- *.1-city.de
- Valid from
- Jul 25, 2026
- Valid until
- Oct 23, 2026 (33 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 059CD950F7051B3BB9A0731B37FAE928FD13
- SHA-256 fingerprint
- 19:2B:B6:01:14:DE:F4:F5:19:E0:81:BC:74:3A:5D:FF:42:51:F7:9F:43:29:B7:6E:DE:7B:B6:0A:5F:05:9F:03
- Chain
- YR1 → Root YR → ISRG Root X1
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
Never get surprised by 1-city.de's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch 1-city.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.
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