Comparison

RPN Calculus vs Codex Calc

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

RPN Calculus

This scientific calculator app for iPad offers a clean RPN interface with basic and advanced functions. It supports high precision calculations and provides an extensive, user-extendable database of scientific constants.

Highlights
  • RPN (Reverse Polish Notation) interface
  • Basic and advanced mathematical functions
  • High precision calculations (up to 15 digits)
  • Extensive scientific constant database
  • User-extendable constant database
  • Memory space for values
Read full description

RPN Calculus is a scientific RPN Calculator for the Apple iPad. RPN Calculus provides basic arithmetic operations as well as advanced mathematic operations like trigonometric, hyperbolic or logarithmic functions. The calculator app provides an unlimited, well, limited by system resources, amount of memory space for values. RPN Calculus performs calculations with a precision of up to 15 digits and supports a number range from -1E127 to 1E127. It's smallest presentable number is 1E-128. RPN Calculus offers a clean and simple layout, very common if you have used scientific RPN calculators before. RPN Calculus has a build in constant values database. The database contains over 120 scientific constants of different categories like e.g. Mathematics, Physics or Astronomy. Since the constants database is user extendable, you can add constant values that you are may be missing in the default set of constants. RPN Calculus can print out your values on the stack and the memory.

About

Codex Calc

This app offers a powerful yet intuitive calculator experience with a variety of modes including scientific, unit conversion, and tip calculation. It features a customizable interface and a detailed history tape for all your calculations.

Highlights
  • Full scientific calculator functions
  • Unit converter
  • Tip calculator
  • RPN mode
  • History tape
  • Customizable interface
  • Multiple visual themes
Features
Read full description

Codex Calc is the calculator for the rest of us: easy and intuitive, without sacrificing power and capabilities. Calculator • Unit Converter • Tip Calculator • RPN Mode • Full Scientific • History Tape All the power you need, wrapped in a beautifully designed interface that's simple without being simplistic. ADAPTS TO YOU Do you like big buttons, or small? Like minimalist interfaces, or are you a fan of bright and flashy? Prefer small fonts to see more detail, or big text and easy to read buttons? Codex Calc adapts itself to the way *you* like to work. FEATURES Everything you'd expect, plus: • History tape records all entries and calculations • Full suite of standard and scientific calculator functions • Unit conversion mode for forward and reverse conversions • Full tip calculator mode - taxes, tip, per-person amounts • RPN mode fully integrated • Rotation lock and sound on/off toggles • Seven different professionally designed visual themes • Multi-number memory and full set of memory-store operators • Full control over history tape font size • Single and multiple-line history tape formats • Large and small button sizes • Settings for customization (number formatting, behavior of clear key, display of calculation details, much more) Calculations: • Trig functions in degrees and radians • Log and power/exponentials • Scientific notation / exponent mode • Rounding and truncating • Random number generation • Parenthesis and sub-expressions ...and more! INTUITIVE TOUCH INTERFACE Take full advantage of your device's capabilities: • Overlays - rather than making buttons smaller to fit more, Codex Calc uses intuitive overlays on the existing buttons. • Popup Menus - hidden until you need them, pop-up context menus give you more power when the default action isn't quite what you need. • Zoomable History Tape - Tap the history tape to expand for more detail, change the font size, copy contents to clipboard, or forward as an email. View as single-lines to save space, or use multi-line view for more detail. • Multiple Flexible Layouts - Portrait and landscape, large and small buttons, and seven different graphical themes. • Easy-Touch Everything - Codex Calc's entire design approach revolves around "touch to activate." Tap the tape to see it bigger, swipe to scroll, long-press a button for more options, tap the display to copy or paste, etc.

Screenshots

Codex Calc4 screens

Verdict

The call

The clearest difference is device support: Codex Calc at 3 against RPN Calculus's 1. Codex Calc also leads on price ($0.99 vs $1.99). On rating, review sentiment, ratings volume and update cadence there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

RPN Calculus costs $1.99 and Codex Calc $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.0 for RPN Calculus against 4.0 for Codex Calc. Both are backed by a comparable volume of ratings — 1 and 1 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

RPN Calculus ships an update every 4 months, Codex Calc every 6 months. The most recent releases landed on October 14, 2026 and October 6, 2026 respectively.

Scorecard2 real differences · 8 level
RPN Calculus versus Codex Calc: the parameters behind the verdict, then further details
ParameterRPN CalculusCodex Calc
Price$1.99$0.99 — better
Rating4.0 (1 ratings)4.0 (1 ratings)
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings11
Update frequencyEvery 4 months — betterEvery 6 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPadiPhone, iPad, iPod — better
Requires iOS12.012.0
Further details — not scored
Size11 MB11 MB
Age rating4+4+
DeveloperThomas BraunDriftwood Studio Software LLC

Customer experience

RPN Calculus

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Codex Calc

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

RPN Calculus

No in-app purchases

None

Codex Calc

No in-app purchases

Questions

Is RPN Calculus free?
RPN Calculus costs $1.99, with no in-app purchases.
Is Codex Calc free?
Codex Calc costs $0.99, with no in-app purchases.
Which has better reviews, RPN Calculus or Codex Calc?
RPN Calculus and Codex Calc are both rated 4.0 out of 5 on the App Store, from 1 and 1 ratings respectively.
Do RPN Calculus or Codex Calc have ads?
Neither RPN Calculus nor Codex Calc shows ads.
Which is updated more often, RPN Calculus or Codex Calc?
RPN Calculus ships an update every 4 months, and Codex Calc every 6 months. Most recently, RPN Calculus was updated on October 14, 2026 and Codex Calc on October 6, 2026.

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