Square footage calculator
Square feet of a room, a deck, a yard or any mix of rectangles, circles and triangles.
A 12 × 14 ft room is 168 square feet, or 18.67 square yards.
Measure each part
Total area
18.67 yd² · 15.61 m² · 0.0039 acre
Everything is calculated in your browser. Nothing you type is sent anywhere.
How to measure square footage
- Measurethe length and the width of each part, wall to wall, in feet and inches.
- Splitan L-shaped or odd room into rectangles, circles and triangles.
- Multiply and addlength × width for each part (π × r² for a circle, ½ × base × height for a triangle), then add the parts.
Square footage of common room sizes
| Room | ft² | yd² | m² |
|---|---|---|---|
| 8 × 10 ft | 80 | 8.89 | 7.43 |
| 10 × 10 ft | 100 | 11.11 | 9.29 |
| 10 × 12 ft | 120 | 13.33 | 11.15 |
| 12 × 12 ft | 144 | 16.00 | 13.38 |
| 12 × 14 ft | 168 | 18.67 | 15.61 |
| 12 × 16 ft | 192 | 21.33 | 17.84 |
| 14 × 16 ft | 224 | 24.89 | 20.81 |
| 15 × 20 ft | 300 | 33.33 | 27.87 |
| 16 × 20 ft | 320 | 35.56 | 29.73 |
| 20 × 20 ft | 400 | 44.44 | 37.16 |
| 20 × 24 ft | 480 | 53.33 | 44.59 |
| 24 × 30 ft | 720 | 80.00 | 66.89 |
All calculators
Concrete and masonry
- Concrete calculatorCubic yards and 40, 60 or 80 lb bags for slabs, footings, post holes and columns.
Measuring
- Square footage calculatorSquare feet of a room, a yard or any mix of rectangles, circles and triangles.
- Cubic yard calculatorLength × width × depth to cubic yards, cubic feet and cubic meters.
Landscaping
- Mulch calculatorCubic yards or 2 and 3 cu ft bags for a bed, over the mulch already there.
- Gravel calculatorCubic yards and tons of gravel for a driveway, a path or a patio base.
- Rock calculatorLandscape rock, river rock and crushed stone in cubic yards and tons.
- Dirt calculatorFill dirt and garden soil in cubic yards, tons and bags, raised beds included.
- Topsoil calculatorTopsoil in cubic yards and tons for a new lawn or a garden.
Painting and roofing
- Paint calculatorGallons for the walls and ceiling of a room, minus doors and windows.
- Roofing calculatorRoof area from the footprint and pitch, squares and shingle bundles.
Floors and fences
- Tile calculatorTiles and boxes for a floor or a wall, with grout joints and extra for cuts.
- Fence calculatorPosts, rails and pickets for a wood fence, and the concrete for the posts.
Frequently asked questions
How do I calculate square footage?
Multiply the length by the width, both in feet. A room 12 ft long and 14 ft wide is 12 × 14 = 168 square feet. Convert inches first: 12 ft 6 in is 12.5 ft.
How do I find the square footage of an L-shaped room?
Split it into rectangles, measure each one and add them up. A 20 × 12 ft living room with an 8 × 10 ft nook is 240 + 80 = 320 square feet. Use "Add another area" in the calculator for each part.
How many square feet are in an acre?
43,560 square feet (NIST Handbook 44). A 100 × 100 ft lot is 10,000 ft², or 0.230 acre.
How do I convert square feet to square yards?
Divide by 9, because a square yard is 3 ft × 3 ft. 168 ft² is 18.67 yd², which is how carpet is often priced.
What is the square footage of a circle?
π × radius². A round patio 10 ft across has a radius of 5 ft: 3.1416 × 5 × 5 = 78.5 square feet.