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.

So the AMORT key on our 10bII calculates interest, principle and balance just like the hardware 10bII. If you want an amortization table or graph, CALC 1 has a separate form you use that will already have the TVM values from the 10bII entered (number of periods, PV, payment). Then you can quickly generate either a periodic or annual table or graph that can be shared.

In addition to the 12C and 10bII reproductions, CALC 1 has other calculators that take the best features of these, and other classic calculators, and combines them with the great tools available on the iPhone and iPad.

CALC 1 has separate calculators for TVM, cash flows, business percentages, statistics, math functions that share data with the reproductions.

CALC 1 also has Function Calculators that provide a consistent and efficient solution to a wide range of financial, business, probability and statistical problems. You can also easily create a graph of the function by entering the range and selecting the independent variable. Solving for a parameter allows you to perform breakeven analysis for any parameter of any function.

The 1 List Statistics calculator has keys to create histograms and box plots of data just by tapping a key.
The 2 List Statistics calculator will now plot the x-y data just by tapping the “plot” key.
The curve fitting calculators will plot scatter plots with the the best fit lines by simply pressing the “plot” key.

The modern features of the CALC 1 calculators include:

Key preview show values on the keys for ALL store or calculate keys.
- Press and hold any key for a hint.
- Lift your finger outside of a key to cancel.
- Great undo support for keys and expressions.
- Chain, algebraic and RPN calculation methods.
- Display 1-4 lines of the stack in the display by swiping up or down.
- Fixed, significant digits and fractions display formats.
- Pinch to quickly change the number of digits.
- Swipe left or right to change CALC 1 calculators.
- History so you can review and share calculations.
- A List Manager to review and edit statistics and cash flow values.
- UOM and currency conversions.
- Customize the list of CALC 1 calculators to your requirements with free downloads.
- Context sensitive documentation and examples for every calculator and utility.
- Video explainers.

If you have any more questions, we have over 100 pages of documentation, examples and videos found at the “App Support” link.

What’s New

Version 4.50

Version 4.50
Minor updates for the latest iOS.

Version 4.41
This is a major free update with a new plotting framework with over 10 new plotting keys for easy plotting of expressions and data to communicate information clearly and efficiently.

Copy, paste, plot!
Copy data to the clipboard, paste it into the List Manager. Then with 1 tap create histograms, box plots, scatter diagrams and more.

The updated 1 List Statistics calculator will plot histograms or 1-5 box plots from list data. It also has new keys for 1 tap calculation of summary stats, percentile, inverse percentile and sorting.

The updated 2 List Statistics calculator will plot list data.
The curve fitting calculators will plot scatter plots with the the best fit lines by simply pressing the “plot” key.

Plot or solve algebraic expressions.

The plots use Apple System Colors that automatically adapt to both light and dark modes, vibrancy and changes in accessibility settings like increased contrast.

Ratings and Reviews

4.0 out of 5
28 Ratings

28 Ratings

babygirlsteph ,

Perfect for teaching my finance students

I teach an upper lever finance class at a local university. The Finance department requires that the students use TI BAs, so I use that primarily for in class examples.
When I prepared for class and write my exams, I always work the examples on CALC 1 to verify my answers. I love how I can export the history details to Notes.
And I also have the inputs for the TVM calculations recorded (N, I/YR, PV, PMT, FV, PYR, CYR and BEG/END) so I can double check all my inputs and answers. Just having the values shown right on the keys prevented a lot of miscalculations. I like that this app also has a 12C that I am very familiar with having taken the CFA. I’d give it an A!

Imhotep VII ,


I usually use an HP 12CP but this has replaced that long standing relationship. Seeing the value on the keys is worth the price of admission. I am amazed by the scope of this app. HP should hire the developer to design their next product.

Tbillhastings ,

Doesn’t CALC correctly

I have been using the HP 12C for 30 years, and thought this app could replace the hardware. Nope! It simply doesn’t calculate correctly, sometimes returning different answers on the same data entry. Shame on these guys.

Developer Response ,

You are mistaken! The 12C reproduction will calculate EVERY example in the 12C manual correctly. You should provide an example to back up your claims. If you have a problem you can use the "Contact" form from the documentation to contact the developer for help.
It has been months since this user has made this claim without providing even one example.

Financial calculations can be difficult. That is why the CALC 1 calculators have features like "Key Preview" and history details (N, i, PV, PMT, FV, BEG/END mode, C flag) so you can verify if the calculator is really "returning different answers on the same data entry". These are features that 30 year old calculators do not have.

Just to be clear, the CALC 1 app contains a reproduction of the 12C as well as modern calculators with key previews, history details and many other features to prevent the errors that this user is claiming. They share data with the 12C so the user can start with the 12C they have been using and then switch to the more modern version.

CALC 1 (previously CalcFxC) has been in the App Store since 2010 and is used regularly. So if if it did not "CALC correctly", I think someone would have noticed by now.


Roger Carey
9.3 MB

Requires iOS 13.1 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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