Port Scanner

Check which common TCP ports are open on a host and what services answer on them.

A port scan tells you which network services a host exposes. Open ports like 80/443 (web), 22 (SSH), 25/587 (mail) or 3306 (MySQL) reveal what the machine is running — useful for verifying your own firewall, confirming a service is reachable, or auditing exposure.

Enter a hostname above to scan its common ports. Only scan hosts you own or are authorised to test.

Frequently asked questions

Is port scanning legal?

Scanning systems you own or have explicit permission to test is fine. Scanning third-party systems without authorisation may be illegal in your jurisdiction — don't do it.

Why is a port shown as filtered?

A filtered port means a firewall dropped the probe with no response, so the scanner can't tell if the service is open or closed behind it.

Which ports does this check?

It probes a set of the most common service ports (web, SSH, mail, databases, etc.) rather than all 65,535 — enough to profile a host quickly.

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