Tools / Networking
Game Server Port Checker
Test whether your game server's port is open and reachable from the public internet. Enter your server's public IP or domain and a port - we attempt a TCP connection from outside your network and tell you if players can reach it. Works for Minecraft, ARK, Rust, Valheim, Palworld and any TCP port. No account, no install.
How to read the result
- Open - the TCP connection succeeded. Players on the internet can reach this port.
- Closed - the host answered but nothing is listening. The server process is probably not running, or it is bound to the wrong port.
- Filtered - no response at all. Usually the port is not forwarded in your router, a firewall is dropping it, or the server binds to
127.0.0.1instead of0.0.0.0. This is the most common "my friends can't join" cause.
TCP and UDP (Steam query)
TCP mode tests raw port reachability - use it for Minecraft, RCON, web panels, and any TCP service. UDP query (A2S) mode speaks the Steam Source query protocol: enter your query port (often the game port or game port + 1) and, if the server answers, you get its live status - name, map, and player count. ARK, Valheim, Rust, Palworld, CS2 and most Source-based games support A2S. Generic UDP open/closed for non-A2S games can't be confirmed from a single probe, so UDP mode reports a response rather than a blanket open/closed. For safety both modes only reach public, internet-routable addresses; private and loopback IPs are refused.
Related tools
Setting up a server? Build its config with our Minecraft RAM calculator, ARK settings generator, or Palworld settings generator.
Skip port forwarding entirely
Port forwarding, firewall rules, and dynamic IPs are the usual reasons a self-hosted server is unreachable. The tool is free and needs no account; if you would rather the ports just work, Supercraft hosts game servers with ports open out of the box - but the check above works against any host.