Carpet Cost Calculator
Estimate carpet order area, roll length, pad, installation and total project cost for identical rectangular rooms.
Default project preview
$3,109.68
Net room area
504 ft²
Carpet cost
$1,975.68
Pad cost
$378.00
Installation cost
$756.00
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Input and output guide
What each value means
The labels and units below are part of this calculator’s visible methodology. Replace every default with measurements or product data from the actual project.
Room length
Enter this project assumption in ft. The current imperial default is 18 ft.
Room width
Enter this project assumption in ft. The current imperial default is 14 ft.
Identical rooms
Enter this project assumption in a unitless value. The current imperial default is 2. Minimum: 1.
Seam and waste allowance
Enter this project assumption in %. The current imperial default is 12 %. Minimum: 0. Maximum: 40.
Carpet roll width
Enter this project assumption in ft. The current imperial default is 12 ft.
Carpet price per area
Enter this project assumption in per ft². The current imperial default is 3.5 per ft². Minimum: 0.
Pad price per area
Enter this project assumption in per ft². The current imperial default is 0.75 per ft². Minimum: 0.
Installation price per area
Enter this project assumption in per ft². The current imperial default is 1.5 per ft². Minimum: 0.
How to read the outputs
Net room area
2 rooms. Default preview: 504 ft².
Carpet cost
order area rate. Default preview: $1,975.68.
Pad cost
net area rate. Default preview: $378.00.
Installation cost
net area rate. Default preview: $756.00.
Roll length equivalent
at 12 ft width. Default preview: 47 linear ft.
Cost per net area
per ft². Default preview: $6.17.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Net area = length × width × room quantity. Carpet order area applies the waste allowance. Total cost adds carpet, pad and installation using the entered rates.
Reviewed project guidance
How to use this estimate in a real project
Last reviewed: August 19, 2026
Estimate carpet, pad and installation cost for repeated rectangular rooms while keeping net floor area separate from seam/waste allowance and fixed roll width.
Calculation steps
- 1Measure each carpeted room at the floor plane and group only truly identical rooms.
- 2Calculate net room area, then apply the seam/pattern allowance to carpet only.
- 3Convert order area to linear roll length using the selected roll width.
- 4Price carpet on order area while pad and installation use the net area unless the quote states otherwise.
Worked numerical example
Two 18 ft × 14 ft rooms contain 504 ft² of floor. With a 12% seam/waste allowance the carpet order area is 564.5 ft². At a 12 ft roll width that is about 47.0 linear ft of carpet before a seam plan changes the cut layout.
Purchasing and rounding
Confirm roll width, dye lot, pattern repeat and seam direction with the flooring supplier. A rectangular area estimate cannot optimize roll cuts across multiple rooms, halls or stairs.
Interpret the result
The cost combines three different bases: carpet on waste-adjusted order area, pad on net area and labor on net area. A professional seam plan can move the final carpet quantity up or down.
Page-specific assumptions
- Rooms are rectangular and use the same carpet.
- Entered carpet rate matches the displayed area unit.
- Pad and labor rates apply to net floor area.
Common mistakes
- Pricing carpet from net area while ignoring roll cuts.
- Mixing square-yard quotes with square-foot inputs.
- Treating stairs or patterned carpet as ordinary rectangular rooms.
Primary and technical references
BuildMeter provides planning estimates, not engineering, architectural, electrical, mechanical, plumbing, permit or code approval. Review the methodology and verify final decisions with product documentation and qualified professionals.
FAQ
Carpet Cost Calculator questions
Why can carpet orders exceed room area?+
Fixed roll widths, seam placement, direction and pattern matching can require extra material.
Is carpet usually priced by square foot or square yard?+
Both are used. Enter a rate matching the displayed unit system and convert supplier quotes consistently.
Does the estimate include stairs?+
No. Stairs need separate measurements and often have different labor rates.