Area Calculator

Area of squares, rectangles, triangles, circles, trapezoids, parallelograms, rhombuses, ellipses and regular polygons.

Your result will appear here

Fill in the fields and press Calculate, or pick one of the examples.

About the Area Calculator

Computes the area of the common plane shapes from their defining measurements, showing the formula with your numbers substituted. Use any unit of length — the area is in that unit squared.

How to use it

Choose the shape.
Enter its measurements.
Press Calculate.

Example

Trapezoid: a = 3, b = 5, h = 4

→ 16

Formulas used

A_{\text{trapezoid}} = \tfrac{1}{2}(a + b)h

Half the sum of the parallel sides times the height.

A_{\text{rhombus}} = \tfrac{1}{2} d_1 d_2

Half the product of the diagonals.

A_{\text{polygon}} = \tfrac{1}{4} n s^{2} \cot\tfrac{\pi}{n}

Regular polygon with n sides of length s.

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About the Area Calculator

How to use it

Formulas used

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About the Area Calculator

How to use it

Formulas used