SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
heise-it.de
SSL/TLS Certificate
SSL/TLS Certificate for heise-it.de
Hostname mismatch- Issued by (CA)
- Let's Encrypt
- Subject
- web04.janssennet.com
- Valid from
- Jun 5, 2026
- Valid until
- Sep 3, 2026 (37 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 060CB470AFDB331F4A89CDDC87228A928C2B
- SHA-256 fingerprint
- 94:47:F9:56:DE:7C:A8:3E:C1:E0:F3:92:5F:B7:F1:C1:D5:28:07:0F:B8:A0:8C:FF:D9:E0:89:91:55:F3:F5:4B
- 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.
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Uptime
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DNS changes
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TLS certificate
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