Enter the length and width of a room or area to get the square footage and acreage. Add as many rooms as you need and the calculator keeps a running total.
Square footage is simply length multiplied by width, where both measurements are in feet. The result tells you how much floor (or wall, or land) area you are dealing with.
A bedroom measures 12 feet long and 10 feet wide. What is its square footage?
One acre equals 43,560 square feet, so divide any sq ft result by 43,560 to get acres.
Working on a project that also involves 3D space? The volume calculator covers boxes, cylinders, and cones. For electrical work on the same project, try the Ohm's law calculator.
Multiply the length by the width, both in feet. For a room that is 12 feet long and 10 feet wide, square footage = 12 x 10 = 120 sq ft. If you measured in inches, divide each measurement by 12 first to convert to feet.
A 12x12 room is 144 square feet. The formula is length x width: 12 x 12 = 144 sq ft.
A 20x20 area is 400 square feet. Multiply 20 x 20 = 400 sq ft.
A 40x60 area is 2,400 square feet. Multiply 40 x 60 = 2,400 sq ft. That equals about 0.055 acres.
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