TCP Port Check
Check if TCP ports are open, closed, or filtered on any host
TCP port scanning helps identify open services and potential security vulnerabilities on network hosts.
Note: Due to browser security restrictions, bulk port scanning uses intelligent simulated data for demonstration purposes. Individual port checks may be limited by CORS policies. For real port scanning, please use professional network tools like nmap.
Port Scanner
Enter a hostname or IP address and configure scan options
What is TCP Port Scanning?
TCP port scanning is a network diagnostic technique used to determine whether specific TCP ports on a target host are open, closed, or filtered. This technology is crucial for network management, security auditing, and troubleshooting.
Main Uses:
- Network Service Discovery: Identify network services running on target hosts
- Security Auditing: Check for unnecessary open ports and assess security risks
- Troubleshooting: Diagnose network connectivity issues and service availability
- Firewall Testing: Verify that firewall rules are correctly configured
- Compliance Checking: Ensure systems meet security policy requirements
TCP Port States:
Open
Port accepts connections, service is listening on this port
Closed
Port does not accept connections, no service listening
Filtered
Firewall or other network device blocks the connection
Timeout
Connection request timed out, may be dropped or delayed
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