Area Calculator

Calculate the area of rectangles, triangles, circles, trapezoids, and parallelograms with this free area calculator.

Calculate Area

Area = length × width = 12 × 8
Area = 1/2 × base × height = 1/2 × 10 × 6
Area = πr² = π × 5²
Area = 1/2 × (b1 + b2) × h = 1/2 × (8 + 14) × 5
Area = base × height = 9 × 4
Your result will appear here.

How area is calculated

Rectangle:
A = l × w

Triangle:
A = 1/2 × b × h

Circle:
A = πr²

Parallelogram:
A = b × h

Why area matters

Area is used in geometry, construction, design, flooring, painting, landscaping, and many everyday measurement problems.

It helps estimate material needs and compare the size of surfaces.

What your result means

Your result shows the area of the selected shape using the dimensions entered. It also includes the formula and supporting values used in the calculation.

This helps you verify your work and understand how the shape’s dimensions affect total area.

Area calculator tips

Frequently asked questions

What is area?

Area is the amount of space inside a two-dimensional shape.

What units are used for area?

Area is written in square units, such as square feet, square meters, or square inches.

What is the difference between area and perimeter?

Area measures the space inside a shape, while perimeter measures the distance around it.

Can I use decimals?

Yes. This calculator supports whole numbers and decimal values.