Port Check

A port check tries to connect to a host on a specific port to see if something answers there. It helps verify if services (games, web servers, SSH, etc.) are reachable from the internet.

• Use “Use my IP” to test your public address. If you’re behind Carrier-Grade NAT (CGNAT), opening ports on your router won’t expose them to the internet.
• Open ports on your router: look for Port Forwarding/NAT. Forward the external port to the internal IP of your device and the correct protocol (TCP/UDP).
• Give the device a stable IP (DHCP reservation/static IP) and allow the port in the device’s firewall as well.
• Ensure the application is actually listening on that port. For UDP, many services don’t reply—no response often appears as “filtered”.
• If you have more than one router (double NAT), forward on both or place the first router in bridge mode.

Some ISPs use CGNAT or block inbound connections. In those cases, a VPN provider that supports port forwarding can help expose a port to the internet.

• AirVPN — offers configurable port forwarding on multiple servers.
• Proton VPN — includes port forwarding on supported plans/servers.