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 sec-it.nl

Valid
Issued by (CA)
Let's Encrypt
Subject
sec-it.nl
Valid from
Jun 5, 2026
Valid until
Sep 3, 2026 (32 days remaining)
Public key
RSA 2048-bit
Serial
0625F0FA6805F2A207A9712DF6B29C8B468D
SHA-256 fingerprint
FC:52:25:E0:BB:C7:8C:37:A8:0B:15:E6:07:8D:E4:1E:53:28:96:34:AE:74:81:86:45:97:AD:5A:4C:4C:F3:47
Chain
YR2 → Root YR → ISRG Root X1
Subject Alternative Names (2)
sec-it.nl, www.sec-it.nl

Certificate Authority Authorization (CAA)

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

Never get surprised by sec-it.nl'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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