Square Footage Calculator
Measure a room, floor, deck or lawn in square feet — add several shapes for L-shaped spaces, subtract cut-outs, mix feet, inches and meters, and estimate material cost.
Free · No sign-upHow to use Square Footage Calculator
- 1. Pick the shape of the first area and its units, then enter the measurements.
- 2. Use + Add another area for L-shaped rooms or several rooms, and tick Subtract for islands or cut-outs.
- 3. Add a waste % (about 10% for flooring and tile) and an optional price.
- 4. Read the total in square feet, square yards and square meters, plus the estimated cost.
Frequently asked questions
How do I calculate square footage?
Multiply length by width in feet. A 12 ft × 10 ft room is 120 square feet. For other shapes, a circle is π × (diameter ÷ 2)², a triangle is ½ × base × height.
How do I measure an L-shaped room?
Split it into two rectangles, measure each, and add them. Enter each rectangle as its own area with + Add another area; the calculator totals them.
How do I convert inches to square feet?
Choose inches as the unit and enter the measurements. The calculator divides square inches by 144 — for example 144 in × 120 in = 17,280 sq in = 120 sq ft.
How much extra flooring should I buy?
Add about 5–10% for straight layouts and 15% or more for diagonal or herringbone patterns, to cover cuts and mistakes. Enter it as the waste percentage.
How many square feet are in a square yard or square meter?
One square yard is 9 square feet and one square meter is about 10.764 square feet. An acre is 43,560 square feet. All are shown in the results.
How do I estimate cost per square foot?
Enter the price per square foot (or per square yard or meter) and the calculator multiplies it by the total area, including your waste allowance.