DNS Insight
Port Scanner
Port Scanner - Check Open Ports
Scan common network ports on a host to check which are open, closed, or filtered.
How It Works
The scanner attempts TCP connections to common ports (21, 22, 80, 443, etc.). Open ports accept connections, closed ports refuse them, and filtered ports don't respond.
Understanding Results
Results show each port's status: Open (service listening), Closed (no service), or Filtered (firewall blocking). Open ports may indicate running services.