Sends SYN packets to detect open ports by half-opening TCP connections.

Which ports should I keep closed?

Close all unused ports to reduce attack surface; only keep services you need exposed.

Does scanning harm the target?

Well-behaved scans send minimal packets and should not harm; however, always scan with permission.

Network Port Checker & Scanner Tool

Scan a server or IP address for open ports and services. Enter a host and port range, then click Scan to detect open ports and check firewall status. Advanced options allow deeper analysis.

About IP Address Port Scanner Tool

The port scanner service enables you to identify which ports are open and which services are running on a remote server or device. By sending raw IP packets, the scanner can detect open ports, determine the operating system, and check for firewall protection. If the host's operating system is recognized, the tool can also estimate its uptime and provide additional network insights.

To start a scan, enter the hostname or IP address and specify the port range you want to check. If the target has a firewall, you can switch to advanced mode and select different scan types for deeper analysis. The default connect() scan is recommended for most users, but options like SYN Stealth may be more effective when firewalls block standard connections. You can also choose the ping method and enable OS detection for more comprehensive results.

For best performance, keep the port range small. If the difference between the start and end port exceeds 500, scans may take a long time or fail to complete. Use a shorter port range for faster and more reliable results. The tool is ideal for network troubleshooting, security assessments, and verifying firewall configurations.