Carpet Calculator: Square Yards, Broadloom Run & Floor Area

Carpet is priced by the square yard — one square yard is 9 sq ft — so the first number is your room area converted to square yards. Multiply length by width, add a waste allowance, then divide by 9. Switch to metric and the tool reports square meters instead.

The second number matters for how it is actually cut. Broadloom carpet comes off a roll in a fixed width, almost always 12 ft (sometimes 15 ft). Your room is covered with full-width strips seamed together, so the running length you buy is the area divided by the roll width. A 12 ft × 15 ft room off a 12 ft roll needs about 15 ft of run, seamed down the middle if the room is wider than the roll.

Real jobs add about 10 % for seams, pattern matching, and trimming — carpet is not cut to the exact inch, and the pile direction has to run the same way across seams. Because rolls are cut to length, the count rounds up.