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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:
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

‘Build a Pythagorean theorem calculator in Calcs Builder in under 5 minutes’

Widget Overview

Understanding widgets as the building blocks of Calcs.com templates

Template Features

Advanced features for Calcs.com templates including material changes, load combinations, and data linking

Common Workflows

‘Typical use cases and examples for Calcs Builder templates’

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