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 spwg.edu.pl

Valid
Issued by (CA)
Let's Encrypt
Subject
spwg.edu.pl
Valid from
Jun 5, 2026
Valid until
Sep 3, 2026 (40 days remaining)
Public key
RSA 4096-bit
Serial
064EF6C71B20FB25F7327C23795AD82A3DD1
SHA-256 fingerprint
95:AC:7F:3B:E1:43:90:2A:D3:E7:08:C4:A8:5D:B4:C9:74:97:1B:19:AA:B6:22:2B:7F:0E:05:3D:AB:70:F0:39
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
spwg.edu.pl, www.spwg.edu.pl

Certificate Authority Authorization (CAA)

The serving CA (Let's Encrypt) is authorized by this domain's CAA records (certum.pl, letsencrypt.org).

Never get surprised by spwg.edu.pl's certificate expiring

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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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