Best BSD-3-Clause Licensed Open Source Repositories

The BSD 3-Clause License, sometimes called the 'New BSD License' or 'Modified BSD License', is one of the oldest and most permissive open-source licenses still in wide use. It lets you use, copy, modify, merge, publish, and distribute the code for any purpose, including commercial and closed-source projects, with almost no strings attached. The only real conditions are that you keep the copyright notice and license text in any copies or substantial portions of the software, and that you don't use the names of the original authors or contributors to promote derived products without their permission. That third clause is what distinguishes it from the older 2-Clause BSD License and gives it its '3-Clause' name.

Unlike GPL-family licenses, BSD-3-Clause carries no copyleft obligation: you're free to build proprietary software on top of it and never release your changes. There's no patent grant either, which is one practical difference from Apache-2.0, though in practice this rarely causes issues for smaller libraries. Because it's short, well understood by legal teams, and imposes almost no compliance burden, BSD-3-Clause is a frequent choice for academic software, language runtimes, and foundational libraries that want the widest possible adoption, including by companies building commercial products on top.

Projects choose BSD-3-Clause when maximizing reuse matters more than ensuring downstream contributions come back to the community. It's especially common in scientific computing and data tooling, where researchers and companies alike need to embed code into other systems without licensing friction. Repos on this page under BSD-3-Clause include Flutter, Django, and scikit-learn, all widely embedded in both open-source and commercial software stacks.