Quick Nmap Port Check

A simple port check to quickly determine the status of an Internet facing service or firewall. Uses the powerful Nmap port scanner. Note that this scan will scan for common services only (21) FTP, (22) SSH, (25) SMTP, (80) HTTP, (443) HTTPS and (3389) RDP. Version detection is enabled.

To scan all ports use the full featured Online Nmap Port Scanner (membership required)

What is this Nmap port check?

The port check will test an IP Address for common open ports. This technique of testing for listening services is known as a port scan. Try our advanced online port scanner that is able to scan any IP Address or IP range and all 655535 ports.

Test Firewall through Port Status

Following results from the port check it is usually possible to determine whether a Firewall is present and blocking all traffic to ports that are not available. If some ports are in a closed state and some filtered this indicates a firewall or router may be blocking traffic but is not necessarily configured correctly as closed ports in most cases should be filtered by the firewall.

More Nmap Resources

Additional resources are available on:

API for the Nmap Port Check (BETA)

In addition to the web form on this page there is another way to quickly check the port status of the four ports. With this simple API, curl or any other HTTP based tool or software can be used to get the status of ports and often the presence of a firewall. Output is of content type text.


The API is designed to be used in an ad-hoc fashion not for bulk queries and is like all our IP Tools is limited to 50 (total) requests from a single IP Address per day.