Mission

The great Goals

Our mission is to make Wiki content available offline, with a primary focus on the contents of Wikipedia and other Wikimedia projects.

The general goals we want to achieve are:

the file format is the most efficient and works on all platforms, embedded devices and desktop computers
the file format is used by all kind of publishers and even outside the Wikimedia community
both reader applications and content files are freely interchangeable
everyone can implement software for this file format because it is in a open and documented standard
there is at least one free implementation which is open source
the free implementation can be used easily in other software to make it easy to use the file format without having to implement it

compresses 900.000 articles (full german Wikipedia beginning 2009) to only 1.3 GB
features a fulltext search index
features native category and image handling similar to MediaWiki
is fully documented on this website - ZIM File Format
if you need help implementing it just contact our mailinglist
we are working on a ZIM File Archive to provide a central place to publish ZIM files including mirroring etc.

is all free and open source (GPL)
is based on ZIMlib, a library written in C++
provides a ZIMwriter to create ZIM files from a HTML dump (eg. a prepared database)
provides a ZIMreader as an example how to read ZIM files; ZIMreader acts as a local webserver
there are some more tools such as the ZIMdumper to have a look into ZIM files or check them

A publisher or distributor of content saved into the ZIM format. While we will make every effort to help those wanting to this we simply do not have the resources to do it ourselves. We do keep an index of known ZIM adopters at our archive page.
This project was started by the enthusiasm of volunteers and is mainly driven by them and not business interests.
Due to the small size of the core development team we might not be able to offer up a specific implementation of the openZim format in your chosen programming language. We hope that by publishing the spec more implementations can be written by the adopters of the format.
In order to construct a format that aligns with our mission and spec the adoption of features will have to fit within the goals of the project.