OpenVibeNet

About the Port Checker

Test whether a port accepts connections from the public internet — the definitive check on whether a port forward, firewall rule or service binding actually works.

• Tests from outside your network, as a real client would
• Common service ports or any custom port
• Distinguishes closed ports from filtered ones

Frequently asked questions

My service runs but the port shows closed — why?

Either a firewall is dropping the traffic, the port forward is missing, or the service is bound to localhost instead of all interfaces.

What is the difference between closed and filtered?

Closed means the host actively refused the connection. Filtered means nothing answered at all, which usually indicates a firewall dropping packets silently.

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