SSL/TLS Certificate Lookup
Check a domain's SSL/TLS certificate — who issued it, when it expires, and whether the chain is trusted
alt-f4.win
SSL/TLS Certificate
SSL/TLS Certificate for alt-f4.win
Self-signed- Issued by (CA)
- *.none.none
- Subject
- *.none.none
- Valid from
- Jun 17, 2026
- Valid until
- Jun 16, 2031 (1789 days remaining)
- Public key
- RSA 2048-bit
- Serial
- 12DDB830F3C7EAA99C63962095C42BAD6F410854
- SHA-256 fingerprint
- 9D:B9:98:F1:22:FD:16:03:F7:FF:F7:89:65:F9:8A:1A:35:2B:DB:F3:5F:60:B6:EF:06:B9:42:5C:97:72:62:69
- Chain
- *.none.none
Certificate Authority Authorization (CAA)
No CAA policy is published for this domain — any certificate authority may issue for it.
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Uptime
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DNS changes
We watch NS, MX, CAA, DNSSEC, CNAME and A/AAAA records, and identify the host, network, and ASN behind them, so a real migration or hijack stands out from routine noise.
TLS certificate
We warn you 30, 14, 7, and 1 days before it expires, and flag it if the issuing authority changes or the certificate is unexpectedly replaced.
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