Carpet & Flooring Calculator
Free carpet and flooring calculator. Estimate square feet, square yards, and material cost for any room, with waste allowance. No signup.
A flooring calculator estimates how much carpet, tile, laminate, or hardwood a room needs, adds a waste allowance, and prices the material by the square foot or square yard.
The area and waste formula
room area = length × widtharea with waste = room area × (1 + waste ÷ 100)square yards = area with waste ÷ 9unit price = price per ft², orprice per yd² ÷ 9when you price by the yardmaterial cost = area with waste × unit price
Waste defaults to 10% and can be set anywhere from 0 to 50%. Carpet is normally quoted by the square yard, while tile, laminate, and hardwood are quoted by the square foot, so the price-per selector converts the unit for you.
Worked example: a 12 × 10 ft room at $3.50 per square foot
Defaults: length 12 ft, width 10 ft, price $3.50 per square foot, 10% waste.
| Step | Calculation | Result |
|---|---|---|
| Room area | 12 × 10 | 120 ft² |
| With 10% waste | 120 × 1.10 | 132 ft² |
| Square yards | 132 ÷ 9 | 14.7 yd² |
| Material cost | 132 × $3.50 | $462 |
If you were buying carpet priced at $3.50 per square yard instead, the calculator converts that to about $0.39 per square foot and the material cost becomes roughly $51. The unit selector is the difference between a plausible number and a wildly wrong one.
Reference: room area and square yards
| Room (ft) | Area | Square yards |
|---|---|---|
| 10 × 10 | 100 ft² | 11.1 yd² |
| 12 × 10 | 120 ft² | 13.3 yd² |
| 12 × 12 | 144 ft² | 16.0 yd² |
| 15 × 12 | 180 ft² | 20.0 yd² |
| 16 × 14 | 224 ft² | 24.9 yd² |
| 20 × 15 | 300 ft² | 33.3 yd² |
Waste is not one number for every material. Carpet laid with a power stretcher often needs only 5–10%, while a diagonal tile layout can consume 15% or more.
| Material and layout | Typical waste |
|---|---|
| Carpet, stretch-in | 5–10% |
| Laminate / engineered | 8–10% |
| Tile, straight lay | 10% |
| Tile, diagonal lay | 15% |
| Hardwood, plank | 10–15% |
Rooms that are not a simple rectangle
Split an L-shaped or T-shaped room into rectangles, run the calculator on each, and add the areas before buying. Closets and alcoves count as floor too. Stairs are measured differently: count each tread and riser, then multiply by the width of the run. Because most flooring is sold in fixed roll or box sizes, an odd shape often forces extra waste, so round up on the total.
Ordering with seams in mind
Rooms wider than the carpet roll need a seam. Carpet commonly comes in 12-foot or 15-foot widths, so a room wider than that must be joined, and matching the pile direction across the seam wastes extra material. That is one reason carpet waste can exceed the 10% default in a large or awkward room. Confirm the roll width with your supplier before you finalise the order.
Common mistakes
- Skipping the waste allowance. Buying the exact area leaves nothing for doorways, seams, and pattern matching.
- Mixing price units. A carpet price per yard and a tile price per foot are not comparable until converted. Use the selector.
- Ignoring direction. Carpet pile and plank patterns run a direction, and an offcut usually cannot be flipped to fit.
- Forgetting underlayment and labor. The material total excludes underlay, adhesive, and installation, which often double the real cost.
How many square yards for a 12 × 10 room?
13.3 square yards for the bare area, or 14.7 once 10% waste is added. That is 132 ft² of material to buy.
What waste percentage should I use for tile?
About 10% for a straight lay and up to 15% for a diagonal or herringbone pattern, where more cuts land on the diagonal.
Does the calculator include installation?
No. It returns material area and cost only. Add underlayment, adhesive or tack strip, and labor for a full budget.
How many square feet are in a square yard?
Nine. Divide square feet by 9 to get square yards, which is the unit carpet is usually priced in.
Flooring area is the same length-by-width measurement used by the paint calculator for walls, and the wallpaper calculator if you are finishing the walls at the same time.