Area Calculator

Rectangle and parallelogram: A x B. Triangle: half of base x height. Circle: pi x r^2. Ellipse: pi x A x B. Trapezoid: half of (A + B) x height. Conversions: 1 sq yd is 9 sq ft, 1 sq m is 10.7639 sq ft, and an acre is 43,560 sq ft.

How do I find the area of an odd shaped room?

Split it into rectangles, work out each one and add them up. Almost every real floor plan is two or three rectangles, and a bay or a curve can be approximated with a triangle or half an ellipse.

How many square feet are in a square yard?

Nine, not three. A square yard is three feet by three feet. This catches people out when buying carpet or sod, which are priced by the square yard.

Do I measure the circle by radius or diameter?

This one asks for the radius, which is half the diameter. If you measured straight across the widest point, halve that figure before entering it.