Enter your room dimensions to find out how many square yards of carpet you need, including waste allowance and estimated cost — ready for the carpet store.
The Square Yard Carpet Calculator is used to quickly calculate key measurements and estimates so you can plan materials, costs, and project scope with confidence.
Measure the longest length and widest width of the room in feet. Include closet areas if you want them carpeted. For L-shaped or irregular rooms, measure each section separately and use our irregular shape calculator.
Carpet rolls come in standard widths: 12 feet and 15 feet. If your room is narrower than the roll width, one strip covers the entire width with no seams. If your room is wider, you'll need multiple strips stitched together — and that creates waste offcuts.
Always add 10% for plain carpet (seams, trimming, doorway transitions). Add 15-20% for patterned carpet — patterns must align at seams, which means cutting away extra material. Our calculator defaults to 10%.
A 15 ft × 12 ft bedroom: Area = 180 ft² ÷ 9 = 20 square yards. With 10% waste = 22 yd². At $30 per square yard = $660 for carpet. Add $90-$130 for padding and $60-$120 for installation. Total budget: ~$800-$900.
What every buyer should know before visiting the carpet store.
Carpet in the US is sold by the square yard. One square yard equals 9 square feet — a 3 ft × 3 ft area. When you see a price like "$30 per square yard," that's equivalent to $3.33 per square foot. Some retailers now show both prices to make comparison easier.
The biggest mistake people make is buying only the exact area they measured. Carpet doesn't come in custom-cut pieces — it comes off a roll, usually 12 feet wide. If your room is 14 feet wide, you'll need two strips: one full 12-foot strip and one 2-foot strip, plus extra for the seam. All those little scraps add up.
When budgeting, don't forget padding ($2-$5 per yd²) and installation ($3-$6 per yd²). Total installed cost is typically 50-80% more than the carpet price alone. A $30/yd² carpet really costs $35-$41/yd² installed with padding. Ask your retailer about "carpet + pad + install" package deals — they're almost always cheaper than buying each separately.
Square yards needed for common room sizes (with 10% waste).
| Room Size (ft) | Square Feet | Square Yards | With Waste (yd²) |
|---|
Common questions about carpet estimation and buying.
Measure the room length and width in feet. Multiply them to get square feet. Divide by 9 to get square yards. Add 10% for waste, seams, and pattern matching. Example: 12 × 15 = 180 ft² ÷ 9 = 20 yd² + 10% = 22 yd².
A 12 × 12 room is 144 square feet or 16 square yards. With 10% waste, order about 17.6 square yards. A 12-foot-wide roll covers this room without seams.
Budget carpet: $10-$20/yd². Mid-range: $20-$40/yd². Premium: $40-$80+/yd². Installation adds $3-$6/yd². Padding costs $2-$5/yd² extra.
Carpet comes in rolls of fixed width. When room dimensions don't match the roll width, you get offcuts. Seams, doorways, closets, and pattern matching also create waste. Plan for 10% extra — up to 20% for patterned carpet.
In the US, carpet is traditionally priced by the square yard. Some stores list both. To convert: 1 square yard = 9 square feet. If carpet is $36/yd², that's $4/ft².
Measure the stair width. For each step: tread depth + riser height + 1 inch for nose tuck. Multiply step length × width × number of steps. Typical stairs: 14 steps × 19" × 36" wide ≈ 6 square yards.
A standard roll is 12 ft × 100+ ft = 133+ yd². That covers about 1,200 ft² — roughly 3-4 average bedrooms. Actual yield depends on room shapes and seam placement.