Port checker

Attempts a TCP connection from this server to the host and port you give it. A closed result can also mean a firewall is silently dropping the connection, not just that nothing is listening.

What is Port checker?

Checks whether a specific TCP port on a host is actually accepting connections — the first troubleshooting step when a service seems unreachable, distinguishing "nothing is listening" from "a firewall is blocking it" (both look similar from outside).

How to use it

Enter a host and port and the tool attempts a real TCP connection from the server, reporting open or closed along with the connection time.

Example

example.com:443 -> open (23 ms)