JD-GUI is a standalone graphical utility designed for decompiling and displaying Java source code from compiled ".class" files. The tool reconstructs readable Java source code from bytecode, allowing users to browse methods and fields through an intuitive graphical interface. The application supports multiple deployment options including JAR files, Windows executables, Mac OSX applications, and Linux packages (DEB/RPM). Users can open files through the file menu, access recently opened files, or use drag-and-drop functionality from their file explorer. JD-GUI provides instant access to decompiled Java code, making it useful for reverse engineering, code analysis, and understanding the structure of compiled Java applications. The tool operates as a cross-platform solution that can be launched through various methods including double-clicking executable files or running via command line with Java.