Almost every material estimate starts with square feet: flooring, paint, sod, concrete, roofing. Odd rooms are just simple shapes added together.
Square footage calculator
Split the space into simple shapes and add them up.
Enter your numbers to see the result.
Formulas
- Rectangle: length x width.
- Triangle: base x height / 2.
- Circle: 3.1416 x diameter² / 4.
An L-shaped room is two rectangles. A bay window is a rectangle plus two triangles.
Conversions
- 1 square yard = 9 sq ft (carpet is often priced this way).
- 1 square meter = 10.764 sq ft.
- 1 acre = 43,560 sq ft.
Measuring tips
Measure to the nearest inch and convert: 6 in is 0.5 ft, 3 in is 0.25 ft. For flooring, measure wall to wall and include closets you are covering.
Frequently asked questions
How do I calculate square footage of a room?
Length x width in feet. For an L-shape, split it into two rectangles and add them.
How many square feet is a 12 x 12 room?
144 sq ft.
How do I convert square feet to square yards?
Divide by 9.