This is the software publisher’s description.
CountryWhois is a utility for identifying the geographic location of an IP address. CountryWhois can be used to analyse server logs, check e-mail address headers, identify online credit card fraud, or in any other instance where you need to quickly and accurately determine the country of origin by IP address.
What makes CountryWhois different is its very high accuracy, unprecedented speed of processing, regular updates that keep the ever-changing IP address database up-to-date, an array of supported import and export formats, command-line mode, and a convenient interface.
CountryWhois was built on the renowned SmartWhois technology developed by TamoSoft since 1997. While CountryWhois is similar to SmartWhois in some respects, it is focused exclusively on IP-to-country identification and doesn't need to contact external Whois servers.