SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
SSL/TLS Certificate for optp.org
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- optp.org
- Valid from
- Jul 14, 2026
- Valid until
- Oct 12, 2026 (83 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 054C4E5AA265172DC1CEA8503BF69CE334B8
- SHA-256 fingerprint
- 54:66:83:4B:EF:02:48:58:DC:78:6F:CE:33:15:66:F8:FA:14:B2:6C:C1:19:2C:0B:67:E0:3F:E0:94:02:B9:D8
- 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.