Under U.S. copyright law, fair use functions as an exemption to the copyright law for educational and socially important purposes such as teaching, research, criticism, commentary, parody, and news reporting. Fair use is determined by balancing the four factors found in the fair use statute. This application can help you organize your thoughts around those factors. No one factor is decisive; instead all factors and some additional questions have to be considered. The result is that a particular use is “likely to be fair” or “not likely to be fair.” There are rarely definitive answers outside of courts.
To that end, this application does not tell you whether a proposed use is fair or not, and does not provide any kind of legal advice. It simply helps you structure your own reflections about the fair use factors, and provides a record for you to keep to show that you considered relevant issues.