Use this free carpet calculator to work out how much carpet a room needs in seconds. Enter the room length and width, the waste allowance, and the price per square yard, and the carpet calculator shows the area, the carpet to order, and the estimated cost instantly — no sign-up, no account, and no personal information needed. Your numbers are calculated in your browser and are not sent to us.
Contents: Formula · How to use · Examples · Tips · FAQ · Related tools
No sign-up required. This carpet calculator works in your browser, so the room sizes you enter are not stored or sent to us.
How to Calculate Carpet With This Carpet Calculator
Carpet is usually sold by the square yard in the United States and by the square metre in the United Kingdom and Canada. This carpet calculator gives you both, so you can order in either unit.
Area = Length × Width; Carpet to order = Area × (1 + Waste ÷ 100); Cost = Carpet to order in square yards × Price per square yard
For example, a 12-foot by 10-foot room has an area of 120 square feet. That is 120 ÷ 9 = 13.33 square yards. With 10% waste, order 13.33 × 1.10 = 14.67 square yards. At $30 per square yard, the cost is 14.67 × $30 = $440.00. One square metre equals 10.764 square feet, and one square yard equals 9 square feet.
How to Use the Carpet Calculator
Measure the longest length and the widest width of the room, in feet or metres, and type them into the first two boxes. Choose the unit you measured in. Then type the waste allowance — 10% is a good default for a rectangular room — and the price per square yard.
Tap Calculate Carpet Needed to see the room area in square feet, square metres, and square yards, plus the amount to order and the estimated cost. For L-shaped rooms, split the room into rectangles, run this carpet calculator for each part, and add the results together.
Carpet Calculator Examples
Example 1 — 12 ft by 10 ft, 10% waste, $30 per square yard. Area = 120.00 sq ft (11.15 sq m, 13.33 sq yd). Order = 14.67 sq yd. Cost = $440.00.
Example 2 — 15 ft by 12 ft, 10% waste, $25 per square yard. Area = 180.00 sq ft (16.72 sq m, 20.00 sq yd). Order = 22.00 sq yd. Cost = $550.00.
Example 3 — 5 m by 4 m, 10% waste, $30 per square yard. Area = 20.00 sq m (215.28 sq ft, 23.92 sq yd). Order = 26.31 sq yd. Cost = $789.35.
These carpet calculator examples show how waste changes the order: the room area alone is never enough, because cutting, matching, and fitting always use extra carpet. A larger waste allowance is wise for patterned carpet and for rooms with many corners.
Carpet Calculator Tips
Measure twice, at the widest points, including doorways and alcoves you want covered. Add extra waste for patterned carpet, because the pattern must line up, and for stairs, which need more cutting than a flat floor.
Check whether the quoted price includes underlay, fitting, and delivery, because those can change the total a lot. For background on measuring a room, see the Better Homes and Gardens guide to measuring for carpet. If you are also tiling a bathroom, the tile calculator can help with that room.
Carpet Calculator FAQ
What does a carpet calculator do? A carpet calculator works out a room's area, adds a waste allowance, and estimates how much carpet to order and what it will cost.
How much waste should I allow? Allow 10% for a simple rectangular room, and 15% or more for patterned carpet, stairs, or rooms with many corners.
Why is carpet sold in square yards? In the United States, carpet is traditionally priced by the square yard. One square yard equals 9 square feet, so divide square feet by 9 to convert.
Can I use metres? Yes. Choose metres, and the carpet calculator converts the area to square feet and square yards for you.
Does the cost include fitting? No, unless the price you enter already includes it. The carpet calculator multiplies the amount to order by the price you enter.
Related Tools
Try the Tile Calculator for floor tiles, the Paint Calculator for wall paint, the Concrete Calculator for slabs, and the Wallpaper Calculator for walls. Return to the PDGPT homepage to browse all free calculators by category.
Sources and Method
Method: This page uses only the formulas stated above: Area = Length x Width; Carpet to order = Area x (1 + Waste / 100); and Cost = Carpet to order in square yards x Price per square yard. Square feet are converted to square yards by dividing by 9, and 1 square metre = 10.764 square feet. The calculation runs in your browser, and no external source is used for the result. Last updated: October 28, 2026