Carpet Calculator
Interior · Updated July 2026
Enter your room dimensions to find how much carpet you need — in square feet and square yards, with a waste allowance for seams and trimming.
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Estimates only. Add extra for waste and confirm with your supplier.
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How much carpet do I need?
Multiply room length × width for square feet, add about 10% for seams and trimming, then divide by 9 for square yards.
Measuring for carpet
Multiply room length by width for square feet, add about 10% for seams and trimming, then convert to square yards (divide by 9) since carpet is often priced that way. Measure at the widest points to allow for cuts.
Seams and padding
Carpet comes in 12-foot-wide rolls, so rooms wider than 12 feet need seams — plan their placement away from high-traffic sightlines. Budget for padding and tack strip too.
How to use this calculator
- 1Measure room length and width in feet.
- 2Set a waste allowance for seams.
- 3Read square feet and square yards.
Frequently asked questions
Why is carpet sold in square yards?
Carpet is traditionally priced per square yard; one square yard equals 9 square feet.
How much carpet do I need?
Room length × width plus about 10% for seams and trimming; divide by 9 for square yards.
Why is carpet sold in square yards?
It's the traditional pricing unit; one square yard equals 9 square feet.
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