Port reachability,
clearly distinguished.

Know whether your ports are reachable from the outside — connected, refused, or timed out, with real measured latency.

Check a port See pricing

What Portpeek does

  • 01 Type a hostname and pick the ports you care about — common service ports preselected, plus one custom port.
  • 02 Portpeek opens a real TCP connection from outside your network. Connected — something answered. Refused — the host answered but nothing is listening. Timed out — the firewall is silently dropping.
  • 03 You get each verdict with the precise measured latency, in milliseconds. No guesswork, no "it might be your firewall."
  • 04 That is all. No accounts, no sign-up, no scheduled alerts. This tool answers when you ask it, and says so.

The three outcomes

CONNECTED

TCP handshake completed. A service is listening on this port and your firewall allows inbound traffic.

REFUSED

The host is reachable, but nothing is listening. The request reached the host and was rejected — check your service config.

TIMED OUT

No response within 10 seconds. A firewall is silently dropping the packet, or the hostname does not resolve.

Who it is for

  • /1
    Developers mid-deployment

    You opened a port, restarted the service, and cannot tell whether the problem is your app, your firewall, or your hosting provider.

  • /2
    Small-business owners

    Your web server, database, or game server is running locally but unreachable from the outside. Portpeek tells you where the gap is.

  • /3
    Anyone debugging connectivity

    When tcpdump is not an option and nc -zv runs from inside the network that cannot see itself.

Platform limits

Backend required. This site requires the Portpeek Cloudflare Worker to be deployed at /api/check. Without it, the check functionality is not available.
Port 25 is not allowed. Outbound SMTP is blocked on this platform; a check would always fail misleadingly.
Port 443 uses TLS (implicit TLS handshake). Latency includes the TLS negotiation, not just the TCP handshake.
Hosts behind Cloudflare may appear unreachable from this tool because the Worker cannot open a TCP socket to a host that is itself behind Cloudflare. The result will read as TIMED OUT — that is a platform limitation, not a result about the user's system.
10-second timeout per port. If a host does not respond within 10 seconds, Portpeek reports TIMED OUT with no latency measurement.
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