Custom Formulas
Tools
Easily set up your own computational app! Create formulas and run them as needed
- Rating
- 4.7
- 76 ratings
- Downloads
- 5.5K+
- on Google Play
- Price
- $3.99
- No in-app purchases
- Updated
- Sep 14
- 2026 · v9.6
Screenshots
About Custom Formulas
This app is easy to use, but unlike simpler apps, multiple entered values can be fed into multiple formulas and multiple output values can be displayed. The output of one formula in a group can be fed into the next by using the same variable name.
Related formulas can be grouped into categories to make them easy to find. e.g. Maths formulas, Surveying formulas, Loan interest formulas etc.
The order of variables displayed to the user can be changed, as can the number of decimal digits of precision shown in the output fields.
Three example formulas are pre-installed with the app. In order of increasing complexity they are: slope percentage, compound interest, and point scale factor. There are also a growing number of formulas available to easily download directly in the app from a web sharing hub. Current categories include health, finance, and surveying.
A formula group can be exported or emailed, allowing you to share your creations with other users of the app.
The results from multiple computations using the same formula can be saved to a CSV file for later viewing in a spreadsheet.
You can view the online help here: https://www.binaryearth.net/CustomFormulasHelp/
What’s new
Version 9.6 · Updated September 14, 2026
9.6: Updated to target Android SDK 36. 9.5: Bug fix. 9.4: Fixed issue with file association. 9.3: Updated to target Android SDK 35. 9.2: Fixed a bug with file association for .cf files. 9.1: Allow entry of formulas in Linear Solver without having to insert *'s between coefficient and variable name. 9.0: Updated calculator tool. 8.9: Updated to target Android SDK 34. 8.8: Updated to target Android SDK 33. 8.7: Bug fix. 8.6: Added min(), max(), and avg() functions which each take two values.
User reviews
Excellent app, but, what would make it even better would be the app database saved somewhere that doesn't need root to play around with. I find it easier to edit the database on the PC. That way I also have a backup copy. Any chance this could be done?
Awesome app, it just takes a little bit of time to figure out how to put in all the information.
Can you add the ability to reorganize the "catagories" and "formulas" on the drop down list. I have tons of formulas and would like to organize/rearrange them.
I was originally looking for a programming app when I found this one. I watched the video and this is above and beyond the functionality I was initially seeking! I would love to see more in depth documentation or a user manual. I received developer feedback on the usage of the 'if()' statement. Turns out I was not u...
Good
I've just spent the last few hours making formulas for tabletop RPG damage calculations and Level Ups. This is amazing! It's easy to learn, but remember to use * and / instead of × and ÷, or your formulas won't run.
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| App | Rating | Price | Installs | Last updated | Compare |
|---|---|---|---|---|---|
| Custom Formulas | 4.7 / 5 | $3.99 | 5,000+ | Sep 14, 2026 | |
| Graphing Calculator | 4.5 / 5 | Free | 50,000+ | Nov 18, 2019 | Compare |
| Class Calc Graphing & Statisti | 4.5 / 5 | Free | 50,000+ | Aug 2, 2025 | Compare |
| CalcKit: All-In-One Calculator | 4.8 / 5 | Free | 1,000,000+ | Aug 23, 2026 | Compare |
| Scientific calculator 36 plus | 4.6 / 5 | Free | 100,000+ | Sep 11, 2026 | Compare |
| Unit Converter & Calculator | – | Free | 100,000+ | Oct 29, 2024 | Compare |
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