Square Feet Calculator
Find the area of a rectangle, triangle or circle in square feet. Works in feet, inches, yards or meters and also shows square yards and square meters.
How the square feet calculator works
Pick a shape, choose your unit and enter the measurements. The calculator converts everything to feet first, then works out the area. Use it for flooring, paint, carpet, sod, tile or any job where you need to know how much surface there is.
The formulas
Example: A room that is 15 ft long and 12 ft wide has an area of 180 sq ft, which is 20 sq yd or 16.72 sq m.
For an L-shaped room, split it into rectangles, calculate each one and add the results. Add 5 to 10 percent extra when you buy materials to cover waste and cuts.
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Frequently asked questions
How do I calculate square feet?
Multiply the length in feet by the width in feet. A room 15 ft by 12 ft is 180 square feet.
How do I convert inches to square feet?
Divide each length in inches by 12 to get feet, then multiply them. Or pick Inches in the calculator and it converts for you.
How many square feet are in a square yard?
There are 9 square feet in one square yard, because a yard is 3 feet on each side.
How do I measure an irregular room?
Split it into rectangles or triangles, find each area and add them together.
How much extra flooring should I buy?
Most installers suggest 5 to 10 percent extra for waste and cuts, more for diagonal patterns.
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