Square Footage Calculator
Multiply length by width in feet: a 12 × 14 ft room is 168 square feet (18.67 sq yd). For an L-shaped space, split it into rectangles and add them.
Area takeoff
Square footage formulas
| Shape | Formula | Example |
|---|---|---|
| Rectangle or square | length × width | 12 × 14 = 168 sq ft |
| L-shape | rectangle A + rectangle B | 240 + 80 = 320 sq ft |
| Circle | π × (diameter ÷ 2)² | 10 ft → 78.54 sq ft |
| Triangle | ½ × base × height | ½ × 10 × 6 = 30 sq ft |
How to measure a room
- Sketch the floor plan on paper, including closets, bump-outs and alcoves you want to count.
- Measure wall to wall along the floor at the longest points, with the tape level and tight. Write down feet and inches.
- Convert inches to decimal feet by dividing by 12 (6 in = 0.5 ft, 9 in = 0.75 ft), or pick inches in the unit menu.
- Break odd shapes into rectangles, triangles and circles. Measure each piece and add them up with “Add another area”.
- For areas you will not cover, such as a kitchen island, measure them and subtract from the total.
- Round up when you buy. Flooring, tile and sod all need extra for cuts; follow the waste allowance on the product.
Measuring walls instead of floors? Wall area is the room's perimeter times the wall height, which is how the paint calculator works. For a roof, multiply the footprint by the pitch factor in the roofing calculator.
Square feet, square yards and square meters
- 1 square yard = 9 square feet (3 ft × 3 ft).
- 1 square foot = 144 square inches (12 in × 12 in).
- 1 square foot = 0.0929 square meters; 1 square meter = 10.764 square feet.
- 1 acre = 43,560 square feet.
Frequently asked questions
How do I calculate square footage?
For a rectangle, multiply length by width in feet. A 12 ft by 14 ft room is 12 × 14 = 168 sq ft. Measure in inches? Multiply and divide by 144, because a square foot is 12 × 12 = 144 square inches.
How do I find the square footage of an L-shaped room?
Split it into two rectangles, find the area of each, and add them. For example, a 20 × 12 ft section plus a 10 × 8 ft section is 240 + 80 = 320 sq ft. Make sure the two rectangles do not overlap.
How many square feet is a 10x10 room?
100 sq ft, which is 11.11 square yards or 9.29 square meters.
How do I convert square feet to square yards?
Divide by 9, because a square yard is 3 ft × 3 ft. 270 sq ft ÷ 9 = 30 sq yd.
How do I calculate the square footage of a circle?
Multiply π (about 3.1416) by the radius squared, where the radius is half the diameter. A 10 ft diameter patio has a 5 ft radius: 3.1416 × 25 = 78.54 sq ft.
Sources
- Paint Calculator, Benjamin Moore. Used for: wall area as perimeter × height in the paint method referenced below.
- Estimating How Much Roofing Is Required, IKO. Used for: roof area = horizontal area × slope factor (referenced below).
Estimates only. Check local codes and your product's label. Found a number that does not match its source? Send a correction.