Carpet Calculator
Find out how much carpet to buy for a room. Get the square yards and square feet with extra for trimming, plus the linear feet to cut from a standard roll width.
- In square feet
- 198 sq ft
- Cut from a 12 ft roll
- 15 linear ft (20 sq yd)
- Room area
- 180 sq ft
How this calculator works
Room area is length × width. An extra percentage covers trimming at the walls and doorways. Carpet is often priced per square yard, which is 9 square feet.
Broadloom carpet comes in fixed roll widths, usually 12 ft. The calculator tries both orientations and picks the one that needs the fewest linear feet from the roll.
For rooms wider than the roll, you will have a seam. Installers place seams away from doorways and heavy traffic.
Example: a 12 × 15 ft bedroom
- Area: 12 × 15 = 180 sq ft, plus 10% = 198 sq ft.
- In square yards: 198 ÷ 9 = 22 sq yd.
- From a 12 ft roll laid across the 12 ft side: 15 linear ft = 180 sq ft = 20 sq yd, with no seam.
Quick reference
| Room size | Square feet | Square yards |
|---|---|---|
| 10 × 10 ft | 110 | 12.22 |
| 12 × 12 ft | 158.4 | 17.6 |
| 12 × 15 ft | 198 | 22 |
| 15 × 20 ft | 330 | 36.67 |
Tips before you buy
- Remember the carpet pad — it is sold by the square foot or yard and needs the room area without the extra.
- Carpet pile should run the same direction across the whole room. Ask the installer to lay out the seams before ordering.
- Stairs need roughly 1 sq yd per step for standard straight stairs.
Frequently asked questions
How do I convert square feet to square yards for carpet?
Divide square feet by 9. A 180 sq ft room is 20 square yards, or 22 square yards with 10% extra.
How much extra carpet should I buy?
About 10% for a simple rectangular room. Rooms with closets, angled walls or seams may need 15% or more.
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Last updated October 25, 2026