Area Calculator

Calculate the area of rectangles, squares, triangles, and circles.

Free to useNo signup requiredRuns in your browserUpdated July 2026

Shape

Length / Base / Radius

Width / Height (not for circle)

Formula / Logic

Rectangle: L×W. Square: side². Triangle: ½×base×height. Circle: π×radius².

Shape:0

Dim1:10

Dim2:5

Result: Shape: Rectangle, Area: 50 sq units

How do I calculate area of an irregular shape?

Divide it into regular shapes, calculate each area, then add them together.

What units does this use?

Input units are consistent (e.g., feet, meters). Output is in square units of the same measure.

How do I calculate area for a room with an L-shape?

Divide the L-shape into two rectangles at the corner, calculate each rectangle area separately, then add them for the total area.

Can I use meters instead of feet for inputs?

Yes, just keep your units consistent throughout. The area output will be in square units matching whatever input measure you choose.