SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
a-square.at
SSL/TLS Certificate
SSL/TLS Certificate for a-square.at
Valid- Issued by (CA)
- Let's Encrypt
- Subject
- a-square.at
- Valid from
- Aug 20, 2026
- Valid until
- Nov 18, 2026 (61 days remaining)
- Public key
- RSA 4096-bit
- Serial
- 062FDFAFED11B386011ECDE07A4F0D056A4B
- SHA-256 fingerprint
- 42:54:EA:67:C7:88:1C:05:7D:41:A5:C3:A2:CC:AB:97:13:78:E5:6A:07:EF:CF:BA:4F:9F:1F:96:BB:61:BC:70
- Chain
- YR2 → Root YR → ISRG Root X1
Certificate Authority Authorization (CAA)
The serving CA (Let's Encrypt) is authorized by this domain's CAA records (letsencrypt.org).
This certificate has been served since Sep 11, 2026.
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Uptime
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DNS changes
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TLS certificate
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