Open port checker

A port is like a numbered door on your internet connection. To host a game server, reach your cameras from outside, or use remote desktop, the right port has to be open and forwarded to the right device. This tool tries to connect to a port on your own public IP address from Cloudflare's network and tells you whether anything answered.

Port shows as closed?

1. Is the app running? The game server, camera, or program has to be on and listening on that port.
2. Set up port forwarding in your router so outside connections on that port go to the right device. Our router login guide shows how to open your router's settings.
3. Check your firewall. Windows Firewall, macOS, or security software may block incoming connections.
4. Check for shared addresses. Some providers, especially mobile and some fiber providers, share one public IP among many customers (carrier-grade NAT). Port forwarding can't work then; ask your provider for a public IP.

Common ports

Only open ports you actually need. An open port exposes that service to the whole internet, so keep its software updated and protected with a strong password.