Calculate square footage
Length, width, unit, and optional waste allowance.
How the square footage calculation works
For a rectangular area, square footage equals length times width with both measurements in feet. If you measure in inches, divide by 12 to get feet first; for yards, multiply by 3; for meters, multiply by about 3.281. A room that is 12 feet by 10 feet is 120 square feet. To know how much flooring or tile to buy, add a waste allowance of around 10 percent for cutting offcuts.
Frequently asked questions
How do I calculate square footage?
For a rectangular area, multiply the length by the width with both measurements in feet. A room that is 12 feet by 10 feet is 120 square feet. This calculator converts inches, yards, and meters to feet first, so you can enter measurements in any of those units.
How do I find square footage from inches?
Divide each measurement in inches by 12 to convert to feet, then multiply length by width. For example, 144 inches by 120 inches is 12 feet by 10 feet, which equals 120 square feet.
How much extra material should I buy for waste?
A common rule is to add 10 percent for cutting and waste on flooring or tile, and more for diagonal or patterned layouts. Enter a waste percentage and the calculator adds it to the total area you need to buy.
How do I calculate the square footage of an L-shaped room?
Split the room into separate rectangles, calculate the square footage of each, and add them together. Measure each section, find its area, then sum the areas for the total.
Is my data saved anywhere?
No. All calculations run entirely in your browser. Nothing you enter is uploaded or saved on a server.
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Disclaimer: Results are provided for general informational purposes only. Always double-check important figures independently.