Tools Port Checker

Port Checker

Check if a TCP or UDP port is open and reachable from the internet. Useful for verifying game servers, web apps, SSH, and more.

Quick:

Port closed? Can't forward ports?

portwarp tunnels bypass NAT, CGNAT, and firewall restrictions - no router configuration needed.

Try portwarp - Free

What Is a Port Checker?

A port checker tests whether a specific port on a computer or server is accessible from the internet. When you host a game server (like Minecraft, FiveM, or Rust), other players need to reach your server through a specific port. If the port is closed, nobody can connect.

Common Reasons a Port Is Closed

  • Port forwarding is not configured on your router
  • Your ISP uses CGNAT (check here)
  • Your firewall is blocking incoming connections
  • The application isn't running or is bound to localhost only
  • Your ISP blocks certain port ranges

How to Open a Port

If your port is closed, you can either configure port forwarding on your router, or use a tunneling service like portwarp to bypass all NAT restrictions automatically.