Carpet is priced per square yard in the US and per square metre elsewhere. Enter your room size to see how much carpet to buy, including extra for seams and trimming, and an optional cost.
Carpet comes in rolls (usually 12 ft or 4 m wide), so the installer may need a little more to keep the pile running the same way — ask for a seam plan on large rooms.
Formula
Square yards = Length (ft) × Width (ft) × (1 + Waste) ÷ 9
There are 9 square feet in a square yard.
Worked example
A 15 × 12 ft bedroom is 180 ft². Adding 10% gives 198 ft², or 22 square yards of carpet.
Frequently asked questions
How do I convert square feet to square yards?
Divide by 9. 180 ft² is 20 yd².
How much extra carpet should I allow?
About 10% for trimming and seams in a simple rectangular room; more for stairs, closets and irregular shapes.
Last updated · Calculations checked by automated tests· Editorial policy