Requirements
Technical
Runs on Microsoft Windows® with a minimum 800x600 resolution screen.
Windows, Word, PowerPoint and Excel are trademarks of Microsoft Corporation.
macOS
To run the program on a Mac, a Windows emulator is necessary such as Parallels or Bootcamp. Using Wine or CrossOver is not recommended.

"In summary, this software was obviously developed by those who have conducted power analyses for numerous proposals. The authors are well aware of the "What ifs?" that we are asked, and that we ask of ourselves, as we conduct power analyses as a part of planning trials. With its great flexibility and speed, this nicely designed software would be well used by anyone involved in the design of clinical trials and other research projects."
Dr. Andrew Leon - Software Review, Controlled Clincal Trials, 20:202-204 (1999)
Power and Precision

Power and Precision is a statistical power analysis software package for calculation of a sample size for a planned study. The program features an unusually clear interface, and many tools to assist the user in developing an understanding of power analysis.