Area Calculator

Find the area of rectangles, triangles, circles, trapezoids, parallelograms, ellipses, sectors and hexagons.

Shape	Rectangle
Length	8
Width	5
Unit (optional)	cm

Shape

Length

Width

Unit (optional)

Rectangle area

40cm²

Area = length × width = 40 cm².

Your rectangle

1
Formula
A = length × width
2
With your measurements
Length = 8, Width = 5 → 40 cm²

About the Area Calculator

Area is the amount of flat space inside a shape, measured in square units. Use the same unit for every side; the answer is in that unit squared. To convert, remember squares scale: 1 m² = 10,000 cm² and 1 ft² = 144 in².

The formula

Rectangle: A = l × w; Triangle: A = ½bh; Circle: A = πr²

Trapezoid: ½(a + b)h
Ellipse: πab
Three sides: Heron's formula

Worked example

Room 4.2 m × 3.5 m

A = 4.2 × 3.5 = 14.7 m²

Questions people ask

How do I find the area of an L-shaped room?

Split it into rectangles, find each area and add them.

What's the difference between area and perimeter?

Area is the space inside (square units); perimeter is the distance around (plain units).