Area Calculator – Addition.site

Calculate the area of common geometric shapes—rectangles, circles, and triangles—quickly and accurately with our free, web‑based area calculator. No downloads or registrations required; just open the page, enter your measurements, and get instant results in square meters (m²) with optional conversions to square feet (ft²) and square kilometers (km²). Totally free and easy to use.

How to Use the Calculator

Choose a Shape
Click the shape drop‑down menu and select rectangle, circle, or triangle.
The input labels update automatically:
- Rectangle: length & width
- Circle: radius (the width field disappears)
- Triangle: base & height
Enter Measurements
Input the numeric values in the corresponding fields.
Values are accepted as decimal numbers (e.g., 12.5).
Calculate
Click the calculate button.
The result appears in the read‑only field as XX.XX m².
The result is rounded to two decimal places.
Copy the Result
Click the result field to copy the area to your clipboard.
A “Copied!” message confirms the action.
Share on X
Click the 𝕏 button to share your calculation on X (formerly Twitter).
View Unit Conversions
Below the result, a table lists the area in:
- m² (square meters)
- ft² (square feet) – multiplied by 10.7639
- km² (square kilometers) – multiplied by 0.000001

Understanding the Calculations

Shape	Formula	Description
Rectangle	`length × width`	The area of a four‑sided figure with opposite sides equal.
Circle	`π × radius²`	The area inside a closed curve where every point is the same distance from the center.
Triangle	`½ × base × height`	The area of a three‑sided figure using one side as the base and the perpendicular distance to the opposite vertex as the height.

All calculations use the standard metric unit of square meters (m²). The conversion table helps translate the result into commonly used imperial or larger metric units.

Practical Use Cases

Home Improvement – Quickly estimate floor space, paint coverage, or flooring requirements.
Gardening & Landscaping – Measure garden beds, patios, or irrigation zones.
Construction & Design – Verify material quantities for walls, roofs, or structural components.
Education – Teach geometry concepts or solve classroom problems with instant feedback.
Real Estate – Determine square footage for listings or property assessments.

Key Features

Responsive Design – Works on desktops, tablets, and smartphones.
Dynamic Labels – Automatically updates input prompts based on selected shape.
Copy & Share – Seamless clipboard copy and X sharing for quick dissemination.
Unit Conversion Table – Instant access to ft² and km² equivalents.
No Ads Interference – Ad placeholders are separate from the calculator interface.

Technical Overview

Built with HTML5, CSS3, and JavaScript.
Uses document.getElementById to retrieve user inputs and display results.
Area calculations are performed in the calculateArea() function.
Conversion factors are defined in an object and applied in a loop to generate the table.
The page includes structured data (schema.org) and Open Graph tags to enhance SEO and social sharing.

Summary

Discover the easiest way to calculate areas of rectangles, circles, and triangles with our free area calculator. Get precise results in square meters, copy them, and share on X. Use the conversion table to see equivalent square feet and square kilometers. Ideal for homeowners, designers, students, and real‑estate professionals looking for quick, accurate area measurements. And best of all it's completely Free!

area calculator