The Calculator Gator

Video Demo of a Visual Calculator

-- Updated July 2018

Feed the Calculator Gator and visualize some math! This free, open-source web tool lets you see positive and negative numbers interact, helping feed our hungry alligator. Check out the demo video below.

Whole units and fractional/decimal units align, combine, and collide as you add, subtract, multiply, divide, and square delectable digits together. It works best on a Chrome browser.

A math toy and math visualization tool

-- Updated December 2017

The Calculator Gator web app is an educational tool for both everyday people and students. When you start to work with positive and negative integers and decimals, sometimes it can be difficult to imagine what's happening with these numbers. Someone might think, "What do we add? What do we take away? What sign should we end up with?" This visual calculator helps you think about these questions. Below is a screenshot of what the app looks like. It's best used on a wide-screen display.

Preview of The Calculator Gator

The app represents positive and negative number quantities as oppositely colored circular units. When added or subtracted, multiplied or divided, the calculator quickly animates the solutions. It is meant to help students go beyond just memorizing math rules without meaning. Hopefully students using it can better connect these numbers and operations with more real-world and intuitive meaning. For example, here is another screenshot of an animation of the multiplication of two whole numbers, represented as 8 rows of 9, or "Eight times nine":

Multiplying on The Calculator Gator

So feed the gator with more delicious numbers! Explore decimals, squaring, and other concepts. If you have feedback on the project, please send me a message. Currently it does not animate division how I'd like, and so I hope to add more to it over time.


  1. Link to The Calculator Gator
  2. See the code on Github