Port Scanner
Online port scanner for common port connectivity checks and open-state analysis to assist service troubleshooting
This tool sends network requests to external APIs for port scanning.
Scan Configuration
Tip: A 500ms delay is added between scans to avoid overwhelming the server. Port range scanning is recommended for no more than 20 ports.
Documentation
What is Port Scanning?
Port scanning is a network security technique used to check which ports on a target host are open, closed, or filtered by a firewall. Each port number corresponds to a specific network service, for example, port 80 is used for HTTP (web service), port 443 for HTTPS (secure web service), and port 22 for SSH (remote login). Through port scanning, system administrators can understand the running status of network services, and security experts can discover potential security risks.
How to Use
Enter a domain name or IP address in the target host input box (e.g., google.com or 192.168.1.1)
Select scan type: common ports, web services, mail services, database, or custom ports
If you select custom, you can enter specific port numbers or port ranges
Click the 'Start Scan' button and wait for the scan to complete
View the scan results to understand the status and service information of each port
You can export the scan results in CSV format for saving and analysis
Port Status Explanation
Security Tips
- Only scan hosts you own or have authorization for. Unauthorized port scanning may violate laws and regulations
- Open ports may pose security risks. It is recommended to regularly check and close unnecessary service ports
- Use firewalls to restrict access to sensitive ports, allowing only necessary IP addresses to connect
- Keep systems and services up to date, and fix known security vulnerabilities in a timely manner
- Use strong passwords and two-factor authentication for important services