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Create a simple area calculator (rectangle area = length × width). This is the fastest way to learn the Calcs Builder basics: Inputs → Equation → Output → Preview
Want a fully written, click-by-click tutorial? Start with Quick Start: Pythagoras Theorem and come back here for a second example.

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What you’ll build

A calculator that takes:
  • Length (L) in ft
  • Width (W) in ft
…and outputs:
  • Area (A) in ft²
Using the equation: A = L × W

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Video walkthrough

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Build steps (quick reference)

If you want to follow along while watching, use this checklist.
1

Create a new calculator

In Calculator Builder, click Create a new calculator, name it Area Calculator, and set a short, unique calculator code (e.g., area-calculator).
2

Add inputs

Add two Input widgets:
  • Length: RefID L, Symbol L, Units ft
  • Width: RefID W, Symbol W, Units ft
3

Add the equation

Add an Equation widget:
  • Output variable: Area with RefID A, Symbol A, Units ft^2
  • Formula: 
    L * W
4

Preview and test

Click Preview and test a couple values:
  • L = 10, W = 2 → A = 20 ft²
  • L = 3.5, W = 4 → A = 14 ft²

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Common gotchas

  • Units: If inputs are in ft, the output should be ft² (area is length squared).
  • Variable naming: Equations reference RefID, so the formula must match exactly (L * W, not Length * Width unless those are your RefIDs).
  • Consistency: Keep units consistent across related inputs to avoid confusing results.

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Key takeaways

This example reinforces the essential Calcs Builder workflow:
  • Name + Code — the calculator code is how your calculator is identified and shared.
  • Inputs — gather the user data (length and width).
  • Equation — define the math (L * W).
  • Preview — validate quickly with sample numbers.

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Next steps

Quick Start: Pythagoras Theorem

Written step-by-step guide with RefID & Symbol tips

Widget Overview

Explore all available widgets

Template Features

Advanced template options

Common Workflows

Real-world examples

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