AppPage.net

Screenshots

  • DB40X screenshot 1
  • DB40X screenshot 2
  • DB40X screenshot 3

About DB40X

DB40X is a high-precision scientific calculator compatible with DB48X and inspired by the legendary HP48 series from Hewlett-Packard. It is not an emulator, but a redesign from scratch, which is faster, and delivers never seen before capabilities like computations in arbitrary precision. Like the original HP48, DB40X supports an unlimited stack, RPN and algebraic operations, complex numbers, based numbers, vectors, matrices, text, symbolic computations, numerical solving and integration, graphing and plotting, statistics, engineering units, and well over 1000 built-in functions. DB40X adds several HP50G capabilities, including a library of equations and constants covering mathematics, physics or chemistry. Using modern technologies, DB40X goes well beyond the original HP48 in many ways: - It is significantly faster, uses less memory, and features a higher-resolution 240x400 pixels graphical display. - Integer and decimal values can have an arbitrarily large number of digits, so you can compute log(pi) with 200 digits in a few keystrokes. - The six function keys feature up to three function per key, giving quick access to up to 18 related functions at a time. - Complex numbers can mix and match polar and rectangular form. - Symbolic operations extend to complex numbers, vectors and matrices. - Based numbers can be in any base from 2 to 36, and support any number of bits, making it easy to emulate a 23-bit or 512-bit processor. - Text is represented using Unicode instead of the proprietary HP encoding, facilitating data exchange with the rest of the world. - Multiple graphs can be distinguished using bitmap patterns. - Engineering units include all the modern evolutions of the SI system, and can be configured by the user, e.g. to integrate currency units with the exchange rate du jour. Converting between USD/hour and EUR/day has never been so easy! - A built-in hyperlinked help system documents functions simply by holding the corresponding key, and combine a quick start guide, a user manual and a reference manual. DB40X will run many user RPL programs as is. However, since it is not an emulator, it will not run any HP binary object, and notably will not run HP48 games or anything involving system RPL. Version 0.7.14 is an early-access release. Please consult https://github.com/c3d/db48x/blob/stable/doc/5-Unimplemented.md for a list of HP48 commands that are not yet implemented. DB40X is part of a family of compatible RPL calculators that include DB48X and DB50X. DB40X lacks the ability to write programs or data to disk, and RPL programs are limited to 40K.

Ratings & reviews

4.7

7 ratings

5 ★ 86% 4 ★ 0% 3 ★ 14% 2 ★ 0% 1 ★ 0%

What’s new

Version 0.9.19 · Updated 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.

App privacy

The developer, Christophe de Dinechin, reported these privacy practices to Apple.

Data Not Collected

The developer does not collect any data from this app.

Alternatives to DB40X

Looking for apps like DB40X? Here are 6 similar apps on the App Store. The highest rated is RPN-55 SD (5.0/5), and 5 of the 6 are free to download.

DB40X vs. alternatives
App Rating Price Last updated Compare
DB40X 4.7 / 5 (7 ratings) Free May 25, 2026
WP 34s 4.7 / 5 (29) Free Mar 24, 2024 Compare
RPN-70 SD 4.7 / 5 (11) Free Oct 17, 2025 Compare
RLM-15CX 4.1 / 5 (18) Free Apr 26, 2024 Compare
WP 31s 4.9 / 5 (15) Free Mar 25, 2024 Compare
RPN-67 NP 4.0 / 5 (4) Free Mar 8, 2024 Compare
RPN-55 SD 5.0 / 5 (8) 1.99 USD Oct 17, 2025 Compare

Compare DB40X with the top alternatives: ratings, updates, ASO score and keyword gaps →