Stair Carpet Calculator
Estimate carpet runner length, required strip width, full rolls and material cost for a straight stair flight with optional landing coverage.
Default project preview
1 rolls
Base stair run
24 ft
Carpet area needed
92.2 ft²
Strips from roll width
3
Runner segments
1
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.
Number of stair treads
Enter this project assumption in a unitless value. The current imperial default is 13. Minimum: 1.
Carpeted tread depth
Enter this project assumption in in. The current imperial default is 11 in.
Carpeted riser height
Enter this project assumption in in. The current imperial default is 7.5 in.
Finished carpet width
Enter this project assumption in in. The current imperial default is 36 in.
Additional landing length
Enter this project assumption in ft. The current imperial default is 4 ft. Minimum: 0.
Trim allowance per side
Enter this project assumption in in. The current imperial default is 2 in. Minimum: 0.
Pattern and fitting allowance
Enter this project assumption in %. The current imperial default is 15 %. Minimum: 0. Maximum: 50.
Carpet roll width
Enter this project assumption in ft. The current imperial default is 12 ft.
Carpet roll length
Enter this project assumption in ft. The current imperial default is 30 ft.
Price per roll
Enter this project assumption in a unitless value. The current imperial default is 420. Minimum: 0.
How to read the outputs
Base stair run
treads, risers and landing. Default preview: 24 ft.
Carpet area needed
includes pattern and fitting allowance. Default preview: 92.2 ft².
Strips from roll width
12 ft roll width. Default preview: 3.
Runner segments
based on entered roll length. Default preview: 1.
Purchased carpet area
full-roll quantity. Default preview: 360 ft².
Carpet cost
carpet rolls only. Default preview: $420.00.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Runner length = steps × (tread depth + riser height) + landing length. Allowance is added, cut width is compared with roll width, and the result is rounded to full entered rolls.
FAQ
Stair Carpet Calculator questions
Why are tread and riser dimensions both included?+
Continuous stair carpet normally covers the horizontal tread and vertical riser for every step.
What is the side trim allowance?+
It adds cutting width beyond the visible finished width so edges can be trimmed or turned according to the installation method.
Does this include carpet pad?+
No. Pad, tack strip, nosing details, fasteners and labor should be estimated separately.