Port Checker
Test whether a TCP port is open and reachable on a public host — from the outside, the way the rest of the internet sees it. Checked from Uptimeify's EU servers.
End the manual growth tax.
Running checks by hand eats valuable agency time. Uptimeify monitors your entire client portfolio from one place — on a fair, organization-wide quota model, on secure EU infrastructure. No per-client fees, no surprises.
Frequently asked questions about Port Checker
Open means a service accepted the TCP connection on that port — something is listening. Closed means the host answered but refused the connection, so nothing is listening on that port. Filtered means there was no answer at all within the timeout, which usually points to a firewall silently dropping the traffic, or a host that is down. The check is made from our servers, so it reflects what an outside client on the public internet sees.
No — and that is by design. The checker refuses to connect to private, loopback or reserved address ranges (such as 10.x, 192.168.x or 127.0.0.1), and it pins the connection to the resolved public IP so a hostname can't be used to reach internal systems. It also checks a single port per request rather than scanning ranges. This keeps the tool safe to offer publicly.
The connection is made from Uptimeify's EU servers, not your browser — the host and port you enter are used only to perform the check and are not stored. As an EU-built, EU-hosted provider, Uptimeify keeps this off US infrastructure and clear of US Cloud Act exposure, which matters for agencies handling client data under GDPR.
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