Open Source Licenses


This page lists all the licenses that have been approved by the OSI via the License Review Process. (For questions about the Public Domain, please see this FAQ entry.)

When choosing a license, first, if at all possible, work with a lawyer to determine the Open Source license that’s best for your project. If your project is important to you, then find someone with legal expertise to help you choose the appropriate Open Source license. All the licenses on this page are OSI-approved, and all are fine for releasing Open Source software. But they are not all exactly the same, and a lawyer who knows your project will best be able to explain the effects of different license choices.

If you don’t have access to a lawyer, then consider using a license from the small group below. Those licenses are widely-used and most likely to be familiar to many people — in particular, to potential users of, and contributors to, your software. But this is not legal advice, and we emphasize again that it is best to get legal advice from your lawyer before choosing a license.

Licenses that are most widely-used and familiar:

(If you would like to discuss adding or removing licenses from the above group, please ask on our license-discuss mailing list.)


Complete list of OSI-Approved Licenses:

These are listed semi-randomly, but we have attempted to put them in very rough order of popularity and broad applicability — with some adjustment for licenses that are popular but only within a particular community (such as a software framework or programming language). The ordering is not written in stone. We welcome data on relative usage; please bring such data to the license-discuss mailing list.

You can also view a list of licenses which have been superceded or retired.