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Financial Calculator
Customizable Calculator

CALC 1 Calculator for iPhone and iPad. 

HP 12C Calculator
CALC 1 now includes both a HP 12C

CALC 1 Financial Calculator


CALC 1 give users clean reproductions of the 12C and 10bII that they will feel comfortable with immediately.

Since CALC 1 contains so many tools, we did not need to add anything to the reproductions. We just share the stack, TVM values and some storage registers so the user can switch between the reproductions and the many CALC 1 tools.

CALC 1 Customizable Calculator 


The best calculator for you is one that you can easily customize to save time and reduce mistakes.


CALC 1 provides a number of ways to create customized calculators starting with copying and pasting existing keys to writing custom JavaScript.

The customizable version has all of the features of the financial version plus customization tools.

See this

Financial Calculator Comparison Chart

to compare the features of CALC 1 to other top paid calculator apps.