Zlib License

The zlib / libpng license is one of the Open Source Initiative and the Free Software Foundation (FSF ) recognized Free / Libre Open Source software license. According to the FSF, it is also compatible with the GNU General Public License.

It implies that the author of the software no liability for any damage which may result from the use Selbiger. The use of the software is free for all, that is even for commercial purposes, under the following three conditions:

The Zlib license includes as well as the BSD license does not copyleft.

As with most free licenses, the license contains a disclaimer which does not distinguish between intent and negligence. Such is not applicable under German law. If the software is, however, at no cost, by § 521 BGB, which is only liable for intent and gross negligence.


Originally designed for the licensing of zlib ( which is the back end of the Unix systems widely used gzip compression ), the zlib license is now used by numerous independent projects. Some of the more popular:

  • The Allegro library
  • The Cube-/Sauerbraten-Game-Engine
  • The Irrlicht graphics engine
  • Nullsoft Scriptable Install System
  • The Simple DirectMedia Layer cross-platform multimedia library (since v1.3 )

License text


German translation

This software is Provided ' as-is ', without any express or implied warranty. In no event will the authors be held liable for any damages Arising from the use of this software.

Permission is granted to anyone to use this software for any purpose, including commercial applications, and to alter it and redistribute it freely, subject to the Following restrictions:

This software is provided without express or implied warranty. In no event will the authors be held liable for any damage arising from the use of this software.

Everyone is permitted for any purpose, including commercial applications to use this software to change and redistribute it freely, provided that the following conditions are met:


  • License text for the Open Source Initiative (English)
  • Comment on zlib license at the FSF (English)
  • FLOSS License