Port Checker
Test whether a TCP port is open or closed on any hostname or IP address.
About Port Checking
This tool attempts to open a TCP connection to the specified port on the target host. If the connection succeeds, the port is open and accepting connections. A closed or filtered port means either the service is not running or a firewall is blocking the connection.
For services that send a banner on connect (such as SSH, FTP, and SMTP), the first line of the server's response is shown. This can help identify the software and version running on that port.
Note: checks are performed from this server's network location. A port that is open from here may be blocked on your own network, and vice versa.