Area Calculator: Find the Area of Any Shape

Calculating area is essential for everything from home improvement projects to math homework. Whether you need the area of a rectangle for flooring, a circle for a garden bed, or a triangle for a roof section, our Area Calculator handles all common shapes. Enter the required dimensions and get the area in your choice of square units instantly.

Area Formulas for Common Shapes

Each geometric shape has its own formula. A rectangle's area is length times width. A triangle's area is half the base times height. A circle's area is pi times the radius squared. A trapezoid's area is half the sum of parallel sides times height. An ellipse's area is pi times the semi-major axis times semi-minor axis.

The calculator supports: rectangle, square, triangle, circle, ellipse, trapezoid, parallelogram, sector, and regular polygon. For irregular shapes, you can break them into smaller regular shapes and calculate each separately.

Using the Area Calculator

Select the shape you want to calculate from the dropdown menu. Enter the required dimensions in your preferred unit (inches, feet, yards, centimeters, meters). The calculator shows the area in square units and provides a visual representation of the shape with labeled dimensions.

You can switch between imperial and metric units at any time. The calculator automatically converts your inputs and shows results in both systems. For irregular shapes, the composite shape mode lets you add multiple shapes together.

Practical Applications

Home Improvement

Calculate floor area for tile, hardwood, or carpet. Measure wall area for paint or wallpaper. Determine countertop area for granite or quartz. Most contractors measure in square feet and materials are sold by the square foot or square meter.

Gardening and Landscaping

Find the area of your lawn for fertilizer or sod. Calculate garden bed area for soil and mulch. Determine pond or patio area for liner or paving stones. Always add 10% for waste and cuts when ordering materials.

Real Estate

Square footage is a key metric in property valuation. Know the difference between gross living area (finished, heated spaces) and total area (including garages, basements, and unfinished spaces). Most real estate listings use gross living area.

Unit Conversion Reference

• Square inches to square feet: Divide by 144
• Square feet to square yards: Divide by 9
• Square feet to square meters: Multiply by 0.0929
• Square meters to square feet: Multiply by 10.764
• Acres to square feet: 1 acre = 43,560 square feet
• Hectares to acres: 1 hectare = 2.471 acres

Real-World Example

You need to install hardwood flooring in a rectangular living room measuring 18 feet by 14 feet, with a bay window area that forms a half-circle with radius 3 feet:

• Rectangle area: 18 × 14 = 252 sq ft
• Half-circle area: (π × 3²) / 2 = 14.14 sq ft
• Total area: 252 + 14.14 = 266.14 sq ft
• Add 10% waste: 266.14 × 1.10 = 292.75 sq ft
• Boxes needed (20 sq ft per box): 293 / 20 = 14.65, round up to 15 boxes

Start Calculating

Use our Area Calculator below for fast, accurate area calculations. Also check our Square Footage Calculator and Volume Calculator for related measurement needs.