Scan open TCP ports on any host or IP address. View port status and common service names.
A port scanner probes a server or host for open TCP ports. Each port corresponds to a network service — for example, port 80 is HTTP, port 443 is HTTPS, and port 22 is SSH. Knowing which ports are open helps with network security auditing, server configuration verification, and firewall testing.
An open port means a service is actively listening for connections. A closed port means no service is running, or a firewall is blocking the connection. Unexpected open ports can be a security risk.