Free42 Binary

Free42 is a software recreation of the HP‑42S scientific programmable calculator and its HP‑82240 printer. It implements the full original instruction set and user interface while adding enhancements such as a larger display, algebraic expression handling, attached units, directories, time‑value‑money functions, and two‑dimensional function plotting. The program runs without requiring any HP ROM image and remains compatible with programs written for the hardware calculator.

The simulator is distributed as open‑source software under GPL‑2, with binaries available for macOS, Windows, Linux, Android, and iOS. Each platform package includes the necessary files to install and run the emulator, and the macOS build requires at least macOS 10.13. The project also offers documentation, FAQs, and a discussion group for user support.

Free42 targets users who need the functionality of the HP‑42S on modern computers and mobile devices, including engineers, scientists, and hobbyists who rely on its programmable scientific capabilities. Its compatibility with existing HP‑42S programs and the added features make it a practical replacement for the original hardware.