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 it-up.cn

Valid
Issued by (CA)
Let's Encrypt
Subject
it-up.cn
Valid from
Jun 15, 2026
Valid until
Sep 13, 2026 (37 days remaining)
Public key
EC 384-bit
Serial
05A9ABC1E8A05D2AA9D0746110AF19959FD7
SHA-256 fingerprint
B3:63:D5:C1:93:DB:B4:C4:E0:1E:67:ED:A8:C0:99:F8:B1:83:BC:D4:96:E9:01:99:3D:39:A2:76:A1:1B:4B:5B
Chain
YE2 → Root YE → ISRG Root X2 → ISRG Root X1
Subject Alternative Names (1)
it-up.cn

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

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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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