DB40X

DB40X

High-precision RPL calculator

7 ratings
3 reviews
Free

Details

  • Released
  • Updated
  • August 21, 2024
  • May 25, 2026

Features

DB40X screenshot #1 for iPhone
DB40X screenshot #2 for iPhone
DB40X screenshot #3 for iPhone
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About

A high-precision scientific calculator inspired by the HP48 series, offering arbitrary precision computations, complex numbers, vectors, matrices, and graphing. It supports RPN and algebraic operations, with over 1000 built-in functions and a hyperlinked help system.

Arbitrary precision computations
RPN and algebraic operations
Complex numbers, vectors, and matrices
Graphing and plotting
Engineering units and conversions
Hyperlinked help system
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What's New in DB40X

0.9.19

May 25, 2026

This release brings an improved constants library with Astronomy and Materials sections, the Quote command, GCD and LCM commands, and several other improvements. See release notes (https://github.com/c3d/db48x/releases/tag/v0.9.19) for details.

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User reviews

Nice but too cluttered looking

I have pretty much every HP emulation that has shown up on the App Store and I still have numerous real ones including a 15, a 16, a 34, a 48, a 67 and a 97 and two from Swiss Micro including their 42. My introduction to computing was the 25C some fifty years ago.

While this new 40 has some incredible functionality, cosmetically it looks far too cluttered. Maybe it’s the wrong fonts, or the fonts are too big and though it’s clearly very powerful, it loses the HP realism, which frankly is a big reason to collect them.

I would love to see an update that addresses the cosmetics.
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Cool program

If you’ve used the hp48, 28, or 50g then do yourself a favor and try it. Much more advanced but faithful to the vision for the 48sx. This is a much more appropriate successor to the hp48sx than the 50g was.

Amazing

This is an incredible calculator whether or not you have used an HP48. It does everything and is easy and intuitive to use, and is getting regular updates. Amazing work!

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FAQ

What is DB40X?

DB40X is a high-precision scientific calculator designed from scratch, inspired by the HP48 series. It offers advanced features like arbitrary precision computations, complex numbers, matrices, and graphing, with over 1000 built-in functions.

Does DB40X support RPN?

Yes, DB40X fully supports Reverse Polish Notation (RPN) operations, along with algebraic operations, catering to users familiar with this input method.

Can DB40X perform calculations with arbitrary precision?

Yes, DB40X allows for computations with an arbitrarily large number of digits for integer and decimal values, enabling high-precision calculations like log(pi) with 200 digits.

What types of mathematical objects does DB40X support?

DB40X supports complex numbers (in polar and rectangular forms), vectors, matrices, text, symbolic computations, numerical solving, integration, graphing, and statistics.

Is DB40X compatible with HP48 programs?

DB40X can run many user RPL programs as is, but it is not an emulator and will not run HP binary objects or system RPL, including HP48 games.

How is the help system in DB40X?

DB40X features a built-in hyperlinked help system that documents functions by holding the corresponding key. It combines a quick start guide, user manual, and reference manual for easy access to information.

What devices is DB40X available on?

DB40X is available for iPhone, iPad, and iPod, running on iOS devices.

How often is DB40X updated?

The latest version is 0.9.17, last updated on March 10, 2026. Version 0.7.14 was an early-access release, indicating ongoing development and updates.