What is the Carpet Area Calculator?
Carpet is most often sold and priced by the square yard, but rooms are usually measured in feet. This calculator bridges that gap: enter your room length and width in feet and it tells you how many square yards of carpet you need, including an optional waste allowance for cutting, seams and pattern matching.
How to use it
Measure the longest length and widest width of your room in feet (round up to the nearest few inches to be safe). Enter both values, then choose a waste allowance — 10% is a common default, but use 15–20% for rooms with awkward shapes, alcoves, or a patterned carpet that must be matched. The result shows the floor area in square feet, the base carpet area in square yards, and the recommended order quantity with waste added.
The formula explained
One square yard equals nine square feet (3 ft × 3 ft). So the floor area in square feet, length × width, is divided by 9 to convert to square yards: $$\text{Sq Yards} = \frac{L \times W}{9}$$ The waste allowance multiplies this by \(\left(1 + \frac{\text{waste}}{100}\right)\) so you order enough material to absorb offcuts.
Worked example
A room measuring 12 ft by 15 ft has a floor area of 180 sq ft. Dividing by 9 gives 20 square yards of carpet. Adding a 10% waste allowance gives $$20 \times 1.10 = 22$$ square yards to order.
FAQ
Why are rooms measured in feet but carpet sold in yards? It is a long-standing trade convention; this tool handles the conversion automatically.
How much waste should I add? Around 10% for simple rectangular rooms, and 15–20% for stairs, L-shaped rooms or patterned carpet.
Does this account for the carpet roll width? No — it gives the area needed. Your supplier may round up to fit standard 12 ft roll widths, which can add extra.
