What waste percentage should I use for carpet?

Use 10% for a simple rectangular room with no pattern. Add 15–20% for rooms with alcoves, bay windows, or irregular shapes. For patterned carpet where you must match repeats, use 20–30% depending on the pattern repeat length.

Why is carpet measured in square yards in the US?

Carpet has traditionally been manufactured and sold in 12-foot-wide rolls in the United States. Since 12 feet equals 4 yards, pricing by the square yard became the industry standard. Most US flooring stores still quote prices per square yard even today.

How do I measure a room for carpet?

Measure the longest length and the widest width of the room, including any alcoves, bay windows, or recesses. Always measure at the widest points even if the room is irregular, then calculate as a rectangle. The waste allowance covers material lost to shape cuts.

Does the calculator work for non-rectangular rooms?

Break the room into separate rectangles, calculate each one, and add the results together. Alternatively, measure the overall bounding rectangle (longest length × widest width) and increase the waste percentage to account for the extra cut-off material.

How many square feet are in a square yard?

One square yard equals 9 square feet (3 ft × 3 ft = 9 sq ft). To convert square feet to square yards, divide by 9. To convert square yards to square feet, multiply by 9.

Should I include closets when calculating carpet?

Yes, if you want carpet in the closet. Measure the closet separately and add it to the room total. If the closet is small, its material often comes from off-cuts generated by the main room, so increasing the waste percentage slightly may cover it.

Carpet Calculator

Name: Carpet Calculator
Availability: InStock
Author: Nham Vu

Enter room dimensions to calculate total carpet area needed, including waste allowance, and get an optional cost estimate.

Room Dimensions

Unit of measurement

Feet Meters Inches

Room size

Length

Width

Waste allowance 10%

0% plain 15% shaped 30% pattern

Carpet price (optional)

$ per sq yd

Leave blank to skip the cost estimate.

Enter room dimensions and click Calculate

Summary

Enter room dimensions to calculate total carpet area needed, including waste allowance, and get an optional cost estimate.

How it works

Choose your unit of measurement — feet or meters.
Enter the room length and width.
Set the waste allowance percentage to cover seams, cuts, and pattern repeats.
Optionally enter the carpet price per square yard or square meter for a cost estimate.
Click Calculate to see the area in all units and your total carpet cost.

Use cases

Estimate carpet quantity before visiting a flooring store.
Compare carpet requirements for multiple rooms in a house.
Calculate total carpet cost when you know the price per square yard.
Account for pattern-matching waste on patterned carpet rolls.
Get yardage figures when ordering from suppliers who sell by the yard.
Plan a bedroom, living room, stairs, or hallway carpet installation.
Convert between square feet, square meters, and square yards automatically.
Provide accurate material estimates for flooring installation bids.

Frequently Asked Questions

Last updated: 2026-06-11 · Reviewed by Nham Vu