SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
gdp-planetarium.org
SSL/TLS Certificate
SSL/TLS Certificate for gdp-planetarium.org
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- www.gdp-planetarium.org
- Valid from
- Sep 17, 2026
- Valid until
- Dec 16, 2026 (58 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 0639948AB738F863434759B08FBC04F39D87
- SHA-256 fingerprint
- AD:E7:B1:04:F3:93:6B:E3:1A:E8:A3:D2:30:F7:C1:7E:E4:A1:A8:10:D4:F8:0E:73:22:84:05:E5:FB:31:76:D8
- Chain
- YR2 → Root YR → ISRG Root X1
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 Oct 9, 2026.
Never get surprised by gdp-planetarium.org's certificate expiring
This is today's certificate. Turn on monitoring and we'll watch gdp-planetarium.org 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, 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.
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