NUnit is a unit-testing framework for all .Net languages. Initially ported from JUnit, the current production release, version 3, has been completely rewritten with many new features and support for a wide range of .NET platforms.

NUnit is Open Source software and NUnit 3 is released under the MIT license. Earlier releases used the NUnit license. Both of these licenses allow the use of NUnit in free and commercial applications and libraries without restrictions.

NUnit 3 was created by Charlie Poole, Rob Prouse, Simone Busoli, Neil Colvin and numerous community contributors. A complete list of contributors since NUnit migrated to GitHub can be found on GitHub.

Earlier versions of NUnit were developed by Charlie Poole, James W. Newkirk, Alexei A. Vorontsov, Michael C. Two and Philip A. Craig.