Free Area Calculator — Squares, Rectangles, Circles, Triangles & Trapezoids

Calculate the area of any common 2D shape by entering its dimensions.

Area Calculator

Shape

Area

How to Use

Select your shape, enter the required measurements (all in the same unit), and click Calculate. Area is returned in square units. For a circle, enter the radius (not diameter). For a triangle, enter the base and the perpendicular height. For a trapezoid, enter both parallel sides and the height between them.

Worked Examples

Circle

Radius5 m

A = π×5² ≈ 78.54 m²

Triangle

Base10 m

Height6 m

A = ½×10×6 = 30 m²

Rectangle

Width12 m

Height4 m

A = 12×4 = 48 m²

Frequently Asked Questions

Area is the amount of 2D space enclosed by a shape, measured in square units (m², cm², ft²). It tells you how much surface a shape covers.

A = πr², where r is the radius and π ≈ 3.14159. For a circle with radius 5m: A = 3.14159 × 25 ≈ 78.54 m².

A = ½ × base × height. The height must be the perpendicular distance from the base to the opposite vertex, not the slant side.

A = ½ × (a + b) × h, where a and b are the two parallel sides and h is the perpendicular height between them.

Free Area Calculator — Squares, Rectangles, Circles, Triangles & Trapezoids

Area Calculator

How to Use

Worked Examples

Frequently Asked Questions

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