ClickGUARD uses a combination of geo-location services to geo-locate IP addresses.
How accurate is the geo-location process?
All geo-location services use and maintain databases of geo-locations for Internet Service Providers. IP addresses are overwhelmingly dynamic and often change locations, therefore no service can claim a 100% accuracy in geo-locating an IP address.
Here's an accuracy estimation guaranteed by services used by ClickGUARD:
Country: 95% - 99% accurate
Region (State): 55% - 80% accurate
City: 50% - 75% accurate