Is anything listening?
Check the port state and whether it is bound only to IPv4, only to IPv6, or to every interface.
Free browser-based developer tool
Choose a port, operating environment, and task. Get copy-ready diagnostic commands without uploading system details or installing anything.
Start with the read-only checks, then compare the listener, process, and HTTP result.
Check the port state and whether it is bound only to IPv4, only to IPv6, or to every interface.
Resolve the listener PID to an application before deciding whether to reconfigure or stop it.
Inspect the response status, headers, and redirect chain separately from basic TCP connectivity.
Safety rule: never paste an unfamiliar termination command into an elevated shell. Read the PID or container name first. Binding a server to 0.0.0.0 can expose it to other devices on the same network.