• Determine loan and mortgage terms
  • Solve math, engineering, and science problems
  • Perform Polar/Rectangular conversions
  • Work in hexadecimal, octal, and binary

What is MathU RPN?

MathU RPN is a Reverse Polish Notation (RPN) scientific and financial calculator for the iPhone and iPad running iOS 9.3 or higher.

The calculator does all calculations with double precision accuracy and has 96 functions including 15 financial functions, 4 number bases and 10 statistical functions. There are 20 memory registers.

Full documentation for MathU RPN is available online (and accessible from the application).


  • Native application that runs directly on the iPhone (available exclusive via the AppStore)
  • Full set of scientific functions
  • Integrated time value of money (TVM) financial functions that follow HP-12C conventions.
  • Date functions
  • Double precision accuracy
  • One, Two or four line display
  • 16 element stack
  • 96 built-in functions (including 15 financial functions and 10 statistical functions)
  • Hex, oct, and bin conversions and bit manipulation functions
  • 20 memory registers

Landscape Keypad

MathU RPN for iPhone supports both a portrait and landscape keypad. Simply rotate the iPhone to switch between landscape and portrait keypads. On iPad, press the rotate button to switch between keypads. iPad also supports a larger keypad. Press to 1x or 2x button to switch.

System Requirements

iPhone or iPad running iOS 15.0 or higher.

General Features

  • App for iPhone and iPad
  • Natural calculator interface
  • Portrait and landscape keypads
  • IEEE Double precision accuracy (about 16 digits)
  • 4 or 16 element stack
  • 30 key keyboard (3 functions per key)
  • 16 digit display with SCI, FIX, and ENG formats. Exponents from -308 to 308.
  • Status indicators for shift state, angle mode, and financial annuity mode.
  • Degrees, radians, and grads angle modes
  • Preferences to set the number of digits, angle mode, number base, display format, wordsize
  • One, two or four line stack display
  • Ability to lock orientation (into portrait or landscape)
  • Split-screen and multitasking support for iOS 13.0 or higher


  • 16 element stack (switchable to 4)
  • 20 global registers (directly accessible via the keyboard)
  • 5 dedicated financial registers
  • stack and register functions: clstk, clreg, clx, x<>y

Scientific Functions

  • sin, cos, tan, sin-1, cos-1, tan-1
  • ln, log, ex, 10x, yx, x2, sqrt, 1/x
  • int, frac, mod, pi
  • deg, rad, hours, H.MS, R->P, P->R

Financial Functions

  • N (number of periods)
  • i (percent interest per period)
  • PMT (payment per period)
  • PV (present value)
  • FV (future value)
  • 12×, 12÷ (annualized period and interest entry)
  • Cf0, Cfj, Nj (Cashflow entry)
  • IRR (internal rate of return)
  • NPV (net present value)
  • AMORT (amortization table)
  • clfin (clear financial registers)
  • Annuity preference (toggle between payments due at the beginning of the period and payments due at the end of the period)

Date Functions

  • date (date in the future and day of week)
  • Δdys (days between dates)
  • Date format preference (M.DY or D.MY)

Statistics Functions

  • Σ+ (accumulate statistics)
  • Σ- (remove data from statistics)
  • mean, std
  • rand (random numbers and random integers)
  • x,r,  y,r (linear fit/regression)
  • %, % change, % total
  • N! (factorial and Gamma function)
  • clstats (clear statistics registers)

Number Base Functions

  • hex, dec, oct, bin
  • modular addition, modular subtraction, modular division, modular multiplication
  • two’s complement (chs)
  • and, or, xor, not
  • shl, shr, asr (shift left, right and arithmetic shift right)
  • maskl, maskr (left and right justified masks)
  • wordsize preference (up to 48 bits)

The MathU RPN comes with a built-in Quick Reference guide (clicking here will open guide in a new window).

Access the guide by clicking the info icon on the calculator app.

Click icons for more info on MathU RPN, or click here to compare MathU calculators.