Port Checker

Check a host or IP address against common TCP ports, follow the scan as it moves through the queue, and see which services answer the knock.

A URL is okay. The checker will use the hostname.

Approved core ports

Only these approved core ports can be checked.

Port presets

One destination scan every 5 minutes. This session can scan 10 more new hosts.

Scanner

Security theater armed

0 / 0
Perimeter sweep 0%
Service probe 0%
Awaiting target No active scan Enter a host and run the check.
Idle
Analysis queue Fresh TCP check, one port at a time
The queue is clear.
Target -
Last Scanned -
Open -
Closed -

Signal Guide

Open means the TCP handshake completed before the timeout.
Closed or filtered means the service refused, blocked, or did not answer.
Scan only hosts you own or have permission to inspect.

Port Checker Questions

What is a TCP port checker?

A TCP port checker tests whether a public host accepts a connection on selected ports, which can help verify web, mail, remote access, DNS, database, and other network services.

What does an open port mean?

An open port means the target completed the TCP connection attempt before the timeout. It does not prove the service is configured correctly or safe.

Why are private IP ranges blocked?

Private, local, loopback, and reserved addresses are blocked so the checker is used only against public hosts and avoids probing internal networks.