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Network
Port Check
Check if a specific TCP port is open on a host
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About this tool
Test whether a single TCP port is open and accepting connections on a given host — useful for verifying a server or service is reachable.
Frequently asked questions
Why does a port I know is open show as closed?
A firewall between our server and the target host may be blocking the connection specifically from our network, even though the port is genuinely open from other locations — port checks are always relative to where the check runs from.
Is checking a port on a site I don't own OK?
A single connection attempt to check if a port is open is standard, low-impact network diagnostics — the same as what your browser does when loading any website. Avoid scanning hosts you don't have permission to test against as part of a wider security assessment.