Is Redmine free?

Yes, Redmine is free. It is an open-source project management web application licensed under the GNU General Public License, which allows users to run, modify, and distribute the software without any licensing fees. This means that Redmine can be used freely for both personal and commercial purposes. However, if you modify the source code and distribute it, you must also make your modified version available under the same GPL license.

While Redmine itself is free, some plugins or hosted versions might require payment for additional features or support.