Calculator

A simple, responsive calculator built with HTML, CSS, and JavaScript. Supports mouse and keyboard input.

Quick start

Open the app directly:

• Double-click index.html

Or serve locally (recommended):

• Python 3: python3 -m http.server then visit http://localhost:8000

Features

• Basic operations: add, subtract, multiply, divide
• Equals, clear (AC), toggle sign (±), percent (%)
• Decimal input
• Keyboard support

Keyboard shortcuts

• Digits: 0–9
• Decimal: .
• Operators: +, -, *, /
• Evaluate: Enter or =
• Clear: C
• Delete last: Backspace
• Percent: %

Project structure

• index.html — markup and calculator controls
• styles.css — layout, theming (light/dark support), responsive styles
• script.js — calculator state, operations, and keyboard handling

Development notes

• No build tools required; pure static files
• Accessible output region with aria-live for display updates
• Thousand separators in display for readability

License

MIT