MIT License

Permissions, conditions and limitations at a glance

Permissions, conditions and limitations are classified using data from choosealicense.com (GitHub, MIT License).

What kind of license is it?

The MIT License is a permissive license originating from the Massachusetts Institute of Technology (MIT). Its text is only three paragraphs, making it easy to read, and it permits use, copying, modification, merging, publishing, distribution, sublicensing and selling. There is just one condition: include the copyright notice and this permission notice in all copies or substantial portions of the software. The last paragraph is a disclaimer stating the software is provided "AS IS" without any warranty or liability for damages.

It is considered the most widely used license in public repositories on GitHub, and well-known projects such as Node.js, Ruby on Rails, jQuery and React use MIT. React is also famous for switching from a "BSD + Patents" combination to MIT in 2017.

What you must do when distributing

• Include the original copyright notice (Copyright (c) year copyright holder) together with the full permission notice.
• The notice obligation does not go away even if you distribute only binaries. It is usually placed in an app's "open source licenses" screen, the manual or a text file distributed with it.
• There is no obligation to disclose source, mark changes or keep the same license. You may modify MIT code and put it in a closed commercial product.

How to apply it

Create a LICENSE (or LICENSE.txt, LICENSE.md) file at the root of your repository, put the text in it, and replace [year] with the year and [fullname] with the copyright holder. This site's generator does that for you. Also stating it in package manager metadata (such as "license": "MIT" in package.json) and as SPDX-License-Identifier: MIT in source file headers lets tools recognize the license automatically.

Common misconceptions

• "MIT has no conditions" — It has a notice requirement. The licenses with no conditions at all are 0BSD, Unlicense and CC0.
• "If I use MIT code, my code must also be MIT" — No. As long as you keep the notice for the imported part, your whole product can be distributed under any license (including proprietary).
• "There are no patent worries at all" — The MIT text has no express patent clause. Many take the view that there is an implied license, but if you need an express patent grant, consider Apache-2.0.
• "Releasing under MIT lets others use my name in advertising" — The license only grants copyright permissions; it does not grant trademark or name rights.

When it fits

It is a good fit for libraries, small utilities and example code that you want as many people as possible to use without restrictions. It is easy for companies to adopt and can go into projects under almost any other license (including the GPL), giving it about the widest ecosystem compatibility. In the Rust and JavaScript ecosystems, projects are often released under MIT OR Apache-2.0 dual licensing to complement the lack of a patent clause (dual licensing guide).

Can MIT code go into another project?

General verdicts for taking code released under this license and distributing it combined into a project under each license below. See other combinations in the compatibility checker →

The content on this site is general information, not legal advice. For actual distribution, contracts or disputes, consult a lawyer or other qualified professional.