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 citsi.ca
Expired- Issued by (CA)
- Let's Encrypt
- Subject
- www.citsi.fulu.ca
- Valid from
- Jun 28, 2024
- Valid until
- Sep 26, 2024 (expired 738 days ago)
- Public key
- RSA 2048-bit
- Serial
- 03A19CFC5E3029FC42317FD451B345371AFB
- SHA-256 fingerprint
- F8:64:74:75:69:77:D5:3F:BE:9F:2F:6F:A0:FD:E3:57:26:21:45:5F:ED:A1:66:0B:7C:8A:8D:9B:64:17:C4:EA
- Chain
- R10 → ISRG Root X1
Certificate Authority Authorization (CAA)
The serving CA (Let's Encrypt) is authorized by this domain's CAA records (globalsign.com, letsencrypt.org, pki.goog, sectigo.com).
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DNS changes
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TLS certificate
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