There is no good rule of thumb to determine the geolocation of Internet IP addresses. While some IP blocks tend to belong to certain countries, other IP blocks are distributed in an almost anarchic fashion. Moreover, the IP distribution is not static but in a continuous mutation with new additions, reallocations and deletions.
AWIPLOC allows you to resolve IPs to Country, City, Region and ISP by providing instant access to our 1400 MB online databases with more than 7.9 million IP ranges.
Our databases are fully indexed and the access is made through an industrial strength blazingly fast multithreaded ISAPI server supporting hundreds of simultaneous connections. You will be surprised by the fastness of the responses.
You are not limited to request information about a single IP address at a time, you can request information about multiple IPs at the same time up.