WinPLOTTR is a Windows-based graphical program designed for analyzing powder diffraction patterns. Developed for Windows 9x/2k/NT, it offers a user-friendly interface to display and analyze various types of diffraction patterns, including those from FullProf, Dicvol, and Treor. The program can handle large data files from synchrotron radiation, neutrons, and X-rays experiments, providing visual insights into the quality of the experiment and the agreement between experimental data and calculated models. WinPLOTTR supports multiple data file formats and includes features for pseudo-3D plotting, background subtraction, peak fitting, and structure determination. It can also serve as a graphical user interface for external crystallographic programs, facilitating the entire diffraction analysis process from peak position determination to structure refinement. The program is available for free download and can be customized using a settings file to adapt to specific user needs.WinPLOTTR is a Windows-based graphical program designed for analyzing powder diffraction patterns. Developed for Windows 9x/2k/NT, it offers a user-friendly interface to display and analyze various types of diffraction patterns, including those from FullProf, Dicvol, and Treor. The program can handle large data files from synchrotron radiation, neutrons, and X-rays experiments, providing visual insights into the quality of the experiment and the agreement between experimental data and calculated models. WinPLOTTR supports multiple data file formats and includes features for pseudo-3D plotting, background subtraction, peak fitting, and structure determination. It can also serve as a graphical user interface for external crystallographic programs, facilitating the entire diffraction analysis process from peak position determination to structure refinement. The program is available for free download and can be customized using a settings file to adapt to specific user needs.