Geolocation software

In computing, geolocation software is software that is capable of deducing the geolocation of a person or object and perhaps their actual location. Sometimes, the geolocation of an object is used to impute the location of its owner or user. For example, on the Internet, the identification of a device's IP address can be used to determine the country and even the city and post/ZIP code, organization, or user the IP address has been assigned to, and then to determine an object's actual location. Other methods include examination of a MAC address, image metadata, or credit card information.

An IP address is assigned to each device (e.g., computer, printer) participating in a computer network that uses the for communication. The protocol specifies that each IP packet must have a header which contains, among other things, the IP address of the sender of the packet.

There are a number of free and paid subscription geolocation databases, ranging from country level to state or city—including ZIP/post code level—each with varying claims of accuracy (generally higher at the country level). These databases typically contain IP address data which may be used in firewalls, ad servers, routing, mail systems, web sites, and other automated systems where geolocation may be useful. An alternative to hosting and querying a database is to obtain the country code for a given IP address through a DNSBL-style lookup from a remote server.

Some commercial databases have augmented geolocation software with demographic data to enable demographic-type targeting using IP address data.

The primary source for IP address data is the regional Internet registries which allocate and distribute IP addresses amongst organizations located in their respective service regions:

Secondary sources include:

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