Port Checker: IP Tool

Port Checker is like having your very own private detective running around on your server. This security tool identifies available services running on your server including which ports are available, which operating system is running and whether there is a firewall in place.
 
The port scanner tool can be used to identify available services running on a server.  It uses raw Internet Provider packets to find out what ports are open on a server or which operating system is running or to check if a server has firewall enabled etc. The service can also detect uptime of a host if the host is running one of the known operating systems which the scanner can analyze to guess uptime. To scan a host just enter the host name or IP address in the box and give a range of ports to scan.  If the host has a firewall enabled then you can try a different type of scan in advance mode which can by pass the firewall in most cases. A scan other than "connect" might take some time to finish but will give you more information about the host OS in case if a firewall is enabled on the host. The IP Geolocation tool helps you find the approximate geographic location of an IP address along with some other useful information including ISP, time zones, area codes, and state etc. Just enter the IP address or the host name you want to locate and press the  "Discover" button and  your IP will be tracked in seconds depending if the information of that IP is present in Port Checker's database. The Reverse IP Lookup tool allows you to find other sites running on a webserver.  An IP address or a domain name can be inputted for which the tool queries search engines and finds out other sites hosted on that server.

Conclusion
Port Checker is a hard working set of free security tools. While it looks at first like a technical nightmare it is in reality an easy to use and very useful tool for discovering port availability, operating systems and whether a firewall is in place. But it keeps on giving too by providing more information on the location of the site and other sites that are attached to it. If you need a free tool to investigate yours or others IP or websites then this free security tool is very good at what it does.