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 s4win.it
Hostname mismatch- Issued by (CA)
- Let's Encrypt
- Subject
- web2.s4win.com
- Valid from
- Jul 18, 2026
- Valid until
- Oct 16, 2026 (42 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 056FE7C95E03DC427E8B1DFC72FA5F83D317
- SHA-256 fingerprint
- AC:4E:F9:73:BA:86:0B:DA:3E:63:E6:E5:CD:08:E6:02:DB:E1:18:8C:67:B4:80:B6:B0:0F:0C:ED:DB:DF:A0:CD
- 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 28, 2026.
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DNS changes
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TLS certificate
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