Area Calculator

Find the area of twelve plane shapes using mixed length units, with the applicable formula and converted result.

Area

15

  • Result unitm2
  • Square meters15

How this was calculated

A = length × width

Dimensions are converted to meters before calculation. Results are then converted to the selected squared or cubed unit.

Formula and method

Select the shape and enter its dimensions. Lengths are converted to meters before applying the shape formula. Rectangle area is lw, triangle area is bh/2, circle area is πr² and regular polygon area is ns²/(4 tan(π/n)). A triangle entered by three sides uses Heron’s formula.

Worked example

A 5 m by 3 m rectangle has area 15 m², approximately 161.458656 ft². A triangle with base 5 m and perpendicular height 3 m has half that area, 7.5 m².

Inputs and limitations

Height is perpendicular to the base, not the sloping side. Ellipse inputs are semi-axes, not full diameters. For a ring the outer radius must exceed the inner radius. Linear conversion factors must be squared to convert areas.

Last updated . Results are estimates for informational purposes only.