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ToolsNetworkOpen Port Scanner
Network

Open Port Scanner

Probe a curated set of well-known TCP ports to see which services are reachable.

Enter a value above and run the check to see results here.

How it works

Probe a curated set of well-known TCP ports to see which services are reachable.

Related tools

IP LookupASN LookupPingGeoIP Lookup

Frequently asked questions

Is the Open Port Scanner tool free to use?+

Yes. The Open Port Scanner runs directly in NetInsight with no signup required. Usage is rate limited per IP address to keep the service fast for everyone.

Are my queries logged?+

Diagnostic inputs are processed to produce your result and are not sold or shared. See our Privacy Policy for full detail on retention.

How accurate are the Open Port Scanner results?+

Results are fetched live from authoritative sources each time you run a check, so they reflect the current state rather than a cached snapshot.

More Network tools

Network

IP Lookup

Geolocation, ASN and network owner for an IP.

Network

ASN Lookup

Look up an autonomous system number.

Network

Ping

Measure round-trip latency to a host.

Network

GeoIP Lookup

Approximate the location of an IP address.