Canyouseeme - Check My Port
It helps you find out the current port status (open/closed) on your connection.
Canyouseeme is a simple and free online tool for checking open ports on your local/remote machine. It's fast and easy. Just enter the port number and check (the result will be either open or closed). (Your IP Address is already selected by default, but it may not detect your IP correctly if you're using a proxy or VPN)