Calculation Expressions Introduction

Introduction to Fulcrum Calculation Field Expressions

Calculation fields can be used to write simple expressions to calculate values dynamically based on inputs from other form fields or any other custom logic. This can be simple ‘total’ calculations or complex equations referencing other calculation fields and even data contained in repeatable sections. Expressions are written in standard JavaScript with some custom functions for accessing form data and record values.


Check out the full documentation on available formulae by browsing the complete list of calculation expressions.


We have a library of examples available for showcasing what you can do with calculation fields. Feel free to contribute your own examples by submitting a pull request.


You can enable verbose error reporting in the app when building or troubleshooting complex expressions by setting SHOWERRORS(true). Another useful way to interactively test expressions is to use the eval() function in combination with a text field and INSPECT(). This allows you to type in your code and immediately inspect how it is being evaluated.

Setting Up An Eval Calculation

Evaluating A Calculation