IP geolocation web server
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Latest commit 9f235e4 Jan 6, 2017 @fiorix committed on GitHub Merge pull request #202 from omercnet/heroku
Add support for Heroku




This is the source code of the freegeoip software. It contains both the web server that empowers freegeoip.net, and a package for the Go programming language that enables any web server to support IP geolocation with a simple and clean API.

See http://en.wikipedia.org/wiki/Geolocation for details about geolocation.

Developers looking for the Go API can skip to the Package freegeoip section below.


This section is for people who desire to run the freegeoip web server on their own infrastructure. The easiest and most generic way of doing this is by using Docker.

See the Server Options below for more information on configuring the server.


Install Docker on Ubuntu 14.04 LTS:

sudo apt-get install docker.io

Install Docker on CentOS 7:

yum install docker

Run the freegeoip web server:

docker run --net=host --restart=always -d fiorix/freegeoip


curl localhost:8080/json/

See the API section below for details.

Other Linux, OS X, or FreeBSD

There are pre-compiled binaries available. You'll have to set up your own init scripts for your system.

There is also a Chef cookbook to deploy it automatically.

Server Options

You can configure the freegeoip web server to listen on a port other than the default 8080, and also listen on HTTPS by passing an ip:port and X.509 certificate and key files.

These and many other options are described in the help. If you're using Docker, you can see them like this:

docker run --rm -it fiorix/freegeoip --help

By default, the Docker image of freegeoip does not provide the web page from freegeiop.net, it only provides the API.

If you want to serve that page, you can pass the -public=/var/www parameter in the command line. You can also tell Docker to mount that directory as a volume on the host machine and have it serve your own page, using Docker's -v parameter.

If the freegeoip web server is running behind a proxy or load balancer, you have to run it passing the -use-x-forwarded-for parameter and provide the X-Forwarded-For HTTP header so the web server is capable of using the source IP address of the connection to perform geolocation lookups when an IP is not provided to the API, e.g. /json/ vs /json/


The current implementation uses the free GeoLite2 database from MaxMind.

In the past we had databases from other providers, and at some point even our own database comprised of different sources. This means it might change in the future.

If you have purchased the commercial database from MaxMind, you can point the freegeoip web server or Go API to the URL of it, or local file, and the server will use it.

In case of files on disk, you can replace with a new version and the freegeoip software will load it automatically. URLs are frequently checked in background, and if a new version of the database is available it is loaded automatically also.


The freegeoip API is served by endpoints that encode the response in different formats.


curl freegeoip.net/json/

Returns the geolocation information of your own IP address, the source IP address of the connection.

You can pass a different IP or hostname:

curl freegeoip.net/json/github.com

To lookup the geolocation of github.com after resolving its IP address, which might be IPv4 or IPv6.

Responses can also be encoded as JSONP, by adding the callback parameter:

curl freegeoip.net/json/?callback=foobar

Same semantics are available for the /xml/{ip} and /csv/{ip} endpoints except the callback parameter.

Metrics and profiling

The freegeoip web server can provide metrics about its usage, and also supports runtime profiling.

Both are disabled by default, but can be enabled by passing the -internal-server=:8081 parameter in the command line. Metrics are generated for Prometheus and can be queried at /metrics even with curl.

HTTP pprof is available at /debug/pprof and the examples from the pprof package work.

Package freegeoip

The freegeoip package for the Go programming language provides two APIs:

  • A database API that requires zero maintenance of the IP database;
  • A geolocation http.Handler that can be used/served by any http server.

tl;dr if all you want is code then see the example_test.go file.

Otherwise check out the godoc reference.

GoDoc Build Status GoReportCard


  • Zero maintenance

The DB object alone can download an IP database file from the internet and service lookups to your program right away. It will auto-update the file in background and always magically work.

  • DevOps friendly

If you do care about the database and have the commercial version of the MaxMind database, you can update the database file with your program running and the DB object will load it in background. You can focus on your stuff.

  • Extensible

Besides the database part, the package provides an http.Handler object that you can add to your HTTP server to service IP geolocation lookups with the same simplistic API of freegeoip.net. There's also an interface for crafting your own HTTP responses encoded in any format.


Download the package:

go get -d github.com/fiorix/freegeoip/...

Install the web server:

go install github.com/fiorix/freegeoip/cmd/freegeoip

Test coverage is quite good and tests may help you find the stuff you need.