Try the Acron RPN Calculator before you buy. The lite version has the following limitations:
- Answers are always displayed as floating point. For instance, the full version knows that the sin(45) = sqrt(2)/2, but the lite version only knows that it is 0.707106...
- Functions that cannot use floating point numbers as input have been disabled. This includes factor, gcd, lcm, factorial, and all of the binary/decimal/hexidecimal integer functions.
- Macros, in-line editing, and statistics are not available in the lite version.

Check out our tutorials at

What’s New

Version 3.1.2

Added haptic feedback

Ratings and Reviews

4.8 out of 5
8 Ratings

8 Ratings

Overpowered Lamp ,

Simply Amazing!

This RPN calculator is totally amazing! I have tried nearly a dozen calculator apps and this is the best one thus far! Love the graphical representation when entering equations!

After using lite version for several weeks, went ahead and bought the full version.

iwastoldineedanickname ,

Simple RPN without gimmicky emulation or skin

So many “HP RPN” calculators out there.. which are mostly useful for reminiscing.

This calculator (even with decimal limits in the Lite version) Just Works Well on an iPhone - FREE to replace standard calculator needs. (I purchased the full version to support the developer, but I’ve yet to need the unlocked features.)

The working equation display is also a SIGNIFICANT improvement compared to intermediate evaluation found in most generic “RPN calculators”.

For developer: can you port Calcscript for Android? 🤗 While this is the best RPN iOS calculator I found, it’s still less powerful.

Industrial Emgineer ,

Good Effort But...

...needs built-in tutorials and UI needs tweaking. Sorry, it’s not ready for this decades long HP user to fork out $ for paid version. Hat’s off for effort though


Scot Senyk
29 MB

Requires iOS 10.0 or later. Compatible with iPhone, iPad, and iPod touch.

Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

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