SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
jsem-dobry-sef.cz
SSL/TLS Certificate
SSL/TLS Certificate for jsem-dobry-sef.cz
Hostname mismatch- Issued by (CA)
- Let's Encrypt
- Subject
- www.jsem-dobry-sef.cz
- Valid from
- Nov 4, 2026
- Valid until
- Feb 2, 2027 (87 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 06F8AF7AFB833F6B2A2578A4F2E09D516638
- SHA-256 fingerprint
- 56:60:64:9C:6D:0A:76:62:1C:F1:3B:20:B0:0D:F1:5F:02:1B:24:EA:4B:37:9C:19:A8:53:9C:1B:DF:CE:30:11
- 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.
We've observed 1 previous certificate for this host. This certificate has been served since Oct 1, 2026.
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Uptime
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DNS changes
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TLS certificate
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