Square Feet to Square Yards

Divide by 9. A 12 × 15 ft room is 180 sq ft, which is exactly 20 square yards. This is the rare conversion with no rounding anywhere in it: a yard is three feet, three squared is nine, and the arithmetic stays clean however large the space.

Why carpet is the reason you are here

Carpet and broadloom were sold by the square yard for most of the last century, and plenty of installers still quote and think that way even where the price tag has moved to square feet. If a quote comes back per square yard and your measurements are in square feet, dividing by nine puts the two on the same footing before you compare anything.

The nine also explains a pricing illusion. A carpet at $30 per square yard and one at $3.50 per square foot sound like different products; the second is $31.50 per square yard, so they are within a few percent of each other.

Roll width changes the answer

Broadloom comes in fixed widths, usually 12 feet, sometimes 15. A room 13 feet wide needs a 15-foot roll, and the three feet trimmed off is waste you pay for. So the square yardage you order is set by how the roll fits the room, not only by the floor area — which is why installer quotes routinely exceed the raw conversion by ten to twenty percent.