Carpet Calculator
Enter your room dimensions to get carpet in square yards and an estimated roll count to order.
Enter your measurements to see what to buy.
How to calculate it
Enter your room dimensions to get carpet in square yards and an estimated roll count to order.
Source: Carpet is sold by the square yard (9 ft²). Carpet rolls are typically 12 ft wide; length needed = room length + waste and pattern repeat.
A 12×15 ft room (180 ft²) with 10% waste = 198 ft² ÷ 9 = 22 sq yd. From a 12 ft roll you need 15 ft + waste ≈ 17 ft of length.
Want the full step-by-step walkthrough? Read our How to Estimate Paint for a Room.
Purchasing & waste guidance
- Carpet is priced and sold by the square yard (9 ft²).
- Standard rolls are 12 ft wide — plan the seam layout to minimize waste.
- Add 10% waste for a simple room, 15–20% for patterned carpet with a repeat to match.
- Don’t forget padding and tack strips — priced separately by the square yard.
Assumptions & what’s included
- Room is a single rectangle; carpet is sold by the square yard (9 ft²).
- Waste allowance covers cuts, seams and pattern repeat.
- Roll estimate assumes a 12 ft wide roll. Price is per square yard and optional; padding is extra.
Frequently asked questions
How much carpet do I need for a 12×12 room?
A 12×12 ft room is 144 ft² = 16 sq yd. With a 10% waste allowance you need about 18 sq yd of carpet. The calculator handles any room size.
How many square feet are in a square yard of carpet?
One square yard equals 9 square feet. Carpet is priced by the square yard, so divide your square footage by 9 to compare prices.
How wide is a roll of carpet?
Most residential carpet rolls are 12 ft wide, with some 13 ft 6 in and 15 ft widths available. Plan seam placement so the roll covers the room width with the least waste.
Related guides
Step-by-step project guides that use this calculator.