Rectangles and squares
Rectangle Area Calculator
Enter the length and width of a rectangular surface. For a square, select equal sides and enter one side length.
Enter your measurements
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How to find the area of a rectangle
Multiply length by width: A = L × W. Measure both sides in the same length unit. If the surface is a square, the two sides are equal and the formula becomes A = s².
Example: a 12 ft by 10 ft room
12 × 10 = 120 ft². That equals approximately 11.15 m², or 13.33 yd².
Measure a floor, wall or rectangular plot
Measure along two adjacent edges. For a wall, enter its width and height as the two side lengths. Subtract the area of doors, windows or other openings separately.
A room with alcoves or several sections can be divided into smaller rectangles. Add their areas, without counting overlapping sections twice. Buying flooring may require extra material for cutting and waste; the result here is the measured area only.
How do I enter feet and inches?
Convert the inches to a fraction of a foot: 12 ft 6 in is 12.5 ft. Alternatively, enter 150 inches and choose inches as the length unit.
Results are rounded for display. Calculations use unrounded values and international foot-based conversions. Enter actual lengths, rather than squared units.