C library for the MaxMind DB file format
C Perl M4 Shell Makefile
Latest commit 8f2ad88 Aug 18, 2016 @oschwald oschwald Update Slack notification



The libmaxminddb library provides a C library for reading MaxMind DB files, including the GeoIP2 databases from MaxMind. This is a custom binary format designed to facilitate fast lookups of IP addresses while allowing for great flexibility in the type of data associated with an address.

The MaxMind DB format is an open format. The spec is available at http://maxmind.github.io/MaxMind-DB/. This spec is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License.

See http://dev.maxmind.com/ for more details about MaxMind's GeoIP2 products.


This library is licensed under the Apache License, Version 2.


From a Tarball

This code is known to work with GCC 4.4+ and clang 3.2+. It should also work on other compilers that supports C99, POSIX 2011.11, and the -fms-extensions flag (or equivalent). The latter is needed to allow an anonymous union in a structure.

To install this code, run the following commands:

$ ./configure
$ make
$ make check
$ sudo make install
$ sudo ldconfig

You can skip the make check step but it's always good to know that tests are passing on your platform.

The configure script takes the standard options to set where files are installed such as --prefix, etc. See ./configure --help for details.

If after installing, you receive an error that libmaxminddb.so.0 is missing you may need to add the lib directory in your prefix to your library path. On most Linux distributions when using the default prefix (/usr/local), you can do this by running the following commands:

$ sudo sh -c "echo /usr/local/lib  >> /etc/ld.so.conf.d/local.conf"
$ ldconfig

From the Git Repository

To install from Git, you will need automake, autoconf, and libtool installed in addition to make and a compiler.

Our public git repository is hosted on GitHub at https://github.com/maxmind/libmaxminddb

You can clone this repository and build it by running:

$ git clone --recursive https://github.com/maxmind/libmaxminddb

After cloning, run ./bootstrap from the libmaxminddb directory and then follow the instructions for installing from a tarball as described above.

On Windows via Visual Studio 2013+

We provide a Visual Studio solution in projects\VS12. This can be used to build both the the library and the tests. Please see the README.md file in the same directory for more information.

On Ubuntu via PPA

MaxMind provides a PPA for recent version of Ubuntu. To add the PPA to your APT sources, run:

$ sudo add-apt-repository ppa:maxmind/ppa

Then install the packages by running:

$ sudo aptitude update
$ sudo aptitude install libmaxminddb0 libmaxminddb-dev mmdb-bin

On OS X via Homebrew

If you are on OS X and you have homebrew (see http://brew.sh/) you can install libmaxminddb via brew.

$ brew install libmaxminddb

Bug Reports

Please report bugs by filing an issue with our GitHub issue tracker at https://github.com/maxmind/libmaxminddb/issues

Dev Tools

We have a few development tools under the dev-bin directory to make development easier. These are written in Perl or shell. They are:

  • regen-prototypes.pl - This regenerates the prototypes in the header and source files. This helps keep headers and code in sync.
  • uncrustify-all.sh - This runs uncrustify on all the code. It runs regen-prototypes.pl first. Please run this before submitting patches.
  • valgrind-all.pl - This runs Valgrind on the tests and mmdblookup to check for memory leaks.

Creating a Release Tarball

Use make safedist to check the resulting tarball.

Copyright and License

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at


Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.