These links are taken from several sources (mainly hpmuseum.org) and our own experience. Please also take a look at our other Resource pages in the menu, in particular the Simulators and Emulators page
Best Modern Resources (2026)
These are the most active and useful sites today for HP calculator enthusiasts, programmers, collectors and repairers:
The Museum of HP Calculators (MoHPC) — The definitive online museum + very active forum with thousands of threads on every model (including your HP-15C CE, HP-41 repairs, and new ARM-based calculators).
MoHPC Forum — The best place to ask questions, share programs, or get repair advice.
HP Calculator Archive – hpcalc.org — The largest collection of programs, emulators, manuals and documentation (over 9,700 files).
HP Calculator Literature — Complete scanned manuals, books and training materials for almost every HP model (including HP-12C, HP-15C, HP-41).
HP-41.org — Dedicated HP-41 site with emulators (V41), modules, programs, manuals and tools.
SwissMicros Technical Resources — Excellent manuals and documentation (especially for Voyager and 41 series).
Plus42 — Free enhanced HP-42S simulator (very popular among HP-12C/15C users).
HP Prime Virtual Calculator & Apps — Official HP emulators and mobile apps.
HPCC – Handheld and Portable Computer Club — Long-running UK club with journal, meetings and archives (still active).
HP Calculators and Computers
- HPCalc.org - Eric Rechlin's website
- Valentin Albillo's pages on hpcalc.org
- Eric Smith's HP Calculator Page Simulators and Technical literature.
- HPCC Handheld And Portable Computer Club
- the biggest HP museum - in Australia!
- Namir Shammas monumental mathematical programs site
- Classic Calculators - Epocalc's Site
HP48/38
- The HP48 Goodies Page by Joe Horn
- hpcalc Eric Rechlin's HP-48, 38 and 28 site.
- A lot of programs in Spanish for the HP 48 in Luis Gallardo's page
Other Calculating and Scientific Instruments
- Old Calculators Pages by Rick Bensene
- Disassembling a Curta Calculator by Greg A. Saville
- Old HP and TI Calculators by Gene Wright
- Otis King's patent calculators by Dick Lyon
- The Analytical Engine by John Walker
- Rskey.org by Viktor Toth
Old Computers
- Paul Pierce's Computer Collection Micros to vacuum tube mainframes.
- The Charles Babbage Institute Center for the History of Information Processing
- Timeline of Microcomputers Ken Polsson
- The Digital Equipment Corporation PDP-8 by Doug Jones
- ENIAC-on-a-Chip (Someone had to do it.)
- Vintage calculators - a lot of links