GeoIP database

A GeoIP database is a large lookup table: a range of IP addresses and, next to it, a country, region, city, time zone and often the ISP and ASN. A website takes the visitor's IP, looks it up in the database and gets an answer in a fraction of a second. This is how IP geolocation works.

There are several such databases, built by different companies. They collect data from IP address registries, routing information, details from network operators and latency measurements. Each company has its own sources and rules, so the answers can differ. None of them is accurate in every case.

Hence a common situation: the same IP shows Kyiv on one website, Zhytomyr on another and only the country without a city on a third. Databases detect the country quite accurately. The city is approximate: an operator may serve a whole region from one node, and the database will place all its subscribers in the city where the equipment stands.

Another reason for differences is update lag. Addresses move between operators and regions, while databases are updated once a week or once a month, and websites do not always use the latest version. This is especially visible in mobile networks, where one address may serve subscribers over a large area.

Accuracy also depends on the address type. For datacenter IPs a database usually shows the city of the data center, and for home IPs the city where the operator registered the range. Mobile addresses are often tied to a large city in the region, even if the subscriber is far from it. So the same country can look different at city level for different proxy types. A database answers only one question: where the address is probably located.

For proxies this matters when you choose a country or city. In Prokso you can choose a country, city or ASN, but every website determines location with its own database. The country usually matches, while the city on a particular website may differ. Read more in the city targeting article.

To see what a database knows about an address, open the My IP page through the proxy. It shows the IP, country, approximate city and ISP (ASN). If the city really matters for your task, also check the address on the website you are going to work with.