How to calculate area
Select the shape and provide its dimensions to calculate the enclosed surface area.
Choose a shape
Select rectangle, square, circle, triangle, parallelogram, trapezium, ellipse, or regular polygon.
Enter dimensions
Fill in each positive length using the same unit, such as centimetres or metres.
Read the result
The calculator applies the shape-specific formula and displays the area in square units.
Frequently Asked Questions
What is the formula for the area of a rectangle?
Multiply the width by the height: <strong>area = width × height</strong>.
How do I calculate the area of a circle?
Multiply π by the radius squared: <strong>area = πr²</strong>.
What dimensions does a triangle need?
Enter its base and perpendicular height. The area is <strong>base × height ÷ 2</strong>.
Can I calculate the area of a trapezium?
Yes. Enter both parallel sides and the height; the formula is <strong>(a + b) × height ÷ 2</strong>.
What units should I use for area?
Use the same unit for every dimension. A result from metre inputs is in square metres; centimetre inputs produce square centimetres.
How is a regular polygon area calculated?
Enter the number of sides and side length. The calculator uses the regular-polygon formula involving the apothem.
Why must dimensions be positive?
Lengths describe physical dimensions, so they must be greater than zero for a meaningful area.