Carpet Calculator
Turn room dimensions into the carpet you actually have to buy — square feet, square yards, rolls off a 12 ft or 15 ft bolt, and an estimated material cost. Adds a waste factor so seams and trim cuts do not leave you short.
How to Use
- Enter the room length and width in feet to set the floor area to be covered.
- Add a waste percentage — 10% for a simple square room, more for stairs, closets, or angled walls.
- Pick your roll width: carpet comes off 12 ft or 15 ft bolts, which determines how the room is cut and seamed.
- Enter the price per square yard to see an estimated material cost.
- Read the square feet, square yards, rolls, and cost, and check the step-by-step Show Work below.
Show Work
Notes
About the Carpet Calculator
Carpet Calculator is a quick, free tool for building, materials estimation and site work. It works in your browser and keeps everything on your device. Turn room dimensions into the carpet you actually have to buy — square feet, square yards, rolls off a 12 ft or 15 ft bolt, and an estimated material cost. Adds a waste factor so seams and trim cuts do not leave you short.
How it works
Enter your figures and the result appears instantly, updating the moment you change anything. There is no submit button and nothing to wait for, so it is easy to try a few what-if numbers and compare the results. Just check each box holds the kind of value it expects.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
Why is carpet sold by the square yard?
Carpet has been priced in square yards for decades, while rooms are usually measured in square feet. One square yard equals 9 square feet, so this tool divides your area by 9 and reports both. If a showroom quotes a per-yard price and your room is in feet, that conversion is exactly where people get the numbers wrong.
How much waste should I add?
Plan on about 10% for a plain rectangular room, 15% for one with closets or jogs, and up to 20% for stairs and hallways where you lose a lot to cuts and the nap direction. Carpet has a pile direction, so all pieces in a room must run the same way, which forces more offcuts than hard flooring.
Why does roll width matter?
Carpet ships on big rolls in fixed widths, usually 12 ft or 15 ft. If your room is wider than the roll, you need a seam, and the leftover strip on a wide roll can be waste you still pay for. Matching roll width to room width is how installers minimize both seams and scrap.
Should I include closets and hallways?
Yes — add them to the area or bump the waste percentage, because they almost always need their own pieces cut from the roll. Closets in particular get carpeted from offcuts, but only if those offcuts run the right direction. When in doubt, measure them in and order a little long.
Do I need to budget for padding and installation separately?
This estimate covers the carpet material only. Padding, tack strip, and labor are typically priced on their own, with padding sold by the square yard much like the carpet. Use the square-yard figure here as the basis for padding too, and get installation quoted per yard at the showroom.
How do I use the Carpet Calculator?
Just type your numbers. The answer shows up right away — there is no button to press. Change anything and it updates by itself.
Does it cost anything or need an account?
No. The tool is completely free, there is no account to create, and it keeps working offline after the page first loads.
Is anything I type uploaded?
No. The tool works entirely on your device, so the values you enter never leave your browser.
Common Use Cases
Carpeting a bedroom or living room
Convert room size into square yards and rolls so you order the right amount in one trip instead of running short mid-job.
Budgeting a re-carpet
Enter a per-yard price to get a quick material cost before you commit to a style or visit the showroom.
Planning stairs and hallways
Add extra waste for the heavy cutting and nap-matching that stairs and runners demand so you are not left short.
Comparing roll widths
See how a 12 ft versus 15 ft roll changes seams and leftover scrap for an oddly sized room.
Checking an installer quote
Run your own square-yard count to make sure a bid matches the room and is not padded with extra material.
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