Category: Productivity


       iOS iPhone

RPN-45 SD is a complete simulation of the scientific hand-held calculator HP-45 from 1973. Powerful enhancements turn the calculator into an amazingly useful tool for the 21st century.


• Photo-realistic look based on an existing device
• Animated keys with adjustable click sound and visual feedback
• Simulation of the HP-45's computation times (may be disabled)
• All functions and operations of the HP-45 fully implemented
• "Secret" stopwatch implemented, extended to 100 hours capacity
• Stopwatch may be preset to current time
• Swipe left across display to correct wrong number entries
• Cut/copy/paste of display value
• Double-tap display to show stack and all memory registers
• Complex numbers may be used in almost all operations
• Non-volatile stack registers
• 18 non-volatile memory registers (9 for complex numbers)
• Non-volatile decimal point setting
• Exponentiation and faculty accept any values
• Hyperbolic functions
• Solve linear equations in two unknowns
• Solve quadratic and cubic equations in one unknown
• Normal distribution, Pearson correlation coefficient of paired variables
• Linear regression with estimates
• Weighted mean
• Permutation, Combination (binomial coefficient)
• Integer and fractional part of a number
• Round number
• Random numbers in any range, integer or real
• Day of the week of any date between Jan 1, 0001 and Dec 31, 9999
• Date and day of the week a number of days in the past or future
• Number of days between two dates
• Indicators for active prefix keys
• Angular mode indicator
• Small values automatically shown in scientfic display mode

Tap the display for some basic hints.

Also available for iPad (RPN-45 HD).

For more information, a manual and sample calculations visit the RPN-45 website:

What users said (iPad version):

"This is by far the best RPN calculator available for the iPad!"

"Great app that I would recommend to anyone who grew up with an HP-45!"

"Calculator works great just like my original HP-45. Worth the price and brings back memories of using the slide rule before getting my HP-45."

"This is one of the most accurate but also nicest looking emulators I have come across for the HP-45, or any vintage HP calculator for that matter."

"With the Super-45 mode functions that were added by the developer, this is an extremely powerful calculator. Very elegant design."

What's new

• HP-45 low-battery warning (all decimal points lit) if iPhone's battery drops below 5%
• Polar-rectangular (and vice versa) conversion extended to hyperbolic mode
• Improved sound volume control
• Better legibility of extra functions
• 64-bit support

Bug fixes:
• Calculator didn't turn itself on (iOS 8 only)
• Fixed display rounding error
• LastX didn't work if RCL / n produced an error


Screenshot 1 of 5

Share with Others

Last changed:
Feb 12, 2015
CuVee Software
26.6 MB

Current Version Average Rating:
5.00 (1)

All Versions Average Rating:
5.00 (6)
Other Apps By This Developer
RPN-67 Free
RPN-67 Pro
RPN-97 Pro
Smart Sudoku