Beginner60 minutesJavaScriptDOMMath

Calculator App Project

Project Objectives

  • Build a functional calculator using JavaScript
  • Practice working with arithmetic operators
  • Implement event handling for button clicks
  • Manipulate the DOM to update the display
  • Handle user input and validation

Prerequisites: Before starting this project, you should complete the JavaScript Operators tutorial.

Project Description

In this project, you'll create a calculator application that can perform basic arithmetic operations. This project will help you understand how to work with JavaScript operators, handle user input, and update the display dynamically.

Your Calculator Should Include:

  • A display area for input and results
  • Buttons for numbers 0-9
  • Buttons for basic operations (+, -, *, /)
  • Clear and equals buttons
  • Basic error handling for invalid operations
  • A clean, user-friendly interface

Getting Started

Step 1: Set Up Your Project Files

Create the following files for your project:

  • index.html - The HTML structure
  • styles.css - CSS styles for your calculator
  • script.js - JavaScript code for calculator logic

Step 2: Create the HTML Structure

Set up the basic HTML structure in your index.html file:

Step 3: Add Basic Styles

Add some basic styles to your styles.css file:

Step 4: Implement Calculator Logic

Add the basic calculator logic to your script.js file:

Challenge Yourself

Once you've completed the basic calculator, try these enhancements:

Advanced Features

  • Add support for decimal numbers
  • Implement keyboard input support
  • Add memory functions (M+, M-, MR, MC)
  • Include scientific calculator functions
  • Add a calculation history feature

Testing Your Calculator

Test your calculator with these scenarios:

  • Basic arithmetic operations (2 + 2 = 4)
  • Multiple operations (2 + 3 * 4 = 14)
  • Division by zero (should show error)
  • Large numbers (check for overflow)
  • Decimal calculations (0.1 + 0.2 = 0.3)