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TCP · Common ports · Real scan

Port Scanner

Scan TCP ports on any host or IP: verify which services are accessible from the internet.

What is Port Scanning?

Port scanning probes a host to discover which TCP ports are open and accepting connections. It's essential for network security auditing and troubleshooting.

Port status meanings

  • Open — port accepts connections, service is running
  • Closed — port is reachable but no service is listening
  • Filtered — firewall is blocking the port (no response)

Only scan hosts you own or have permission to test.