SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
opti-act.ch
SSL/TLS Certificate
SSL/TLS Certificate for opti-act.ch
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- opti-act.ch
- Valid from
- Jul 12, 2026
- Valid until
- Oct 10, 2026 (59 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 05B2A800333C99689B32ADF0C1B5E3843A67
- SHA-256 fingerprint
- 79:21:45:44:DF:76:C7:FD:0C:A0:51:F4:99:6D:42:C6:B0:C8:1D:2D:1B:1D:A8:38:5C:9B:0B:12:54:DE:8A:25
- 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.
This certificate has been served since Aug 7, 2026.
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Uptime
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DNS changes
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TLS certificate
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