This carpet calculator estimates the quantity needed for one or more spaces, including a cutting allowance. Choose an area or carpet roll estimate, then add optional carpet, underlay and fitting prices to estimate your costs.
Enter your space measurements and choose an area or roll estimate. Adjust the cutting allowance, then add optional prices if you need a cost estimate.
Select your measurement unit and shape, then enter the dimensions shown in the diagram. For an L-shaped space, measure two rectangles that do not overlap. Choose “Custom area” if you already know the measured area, and enter it in the displayed square unit. Changing the shape clears that area’s dimension fields.
Select “Add another area” for additional spaces, counting each section once. The cutting allowance starts at 10%; adjust it for your layout and installer’s advice. Enter the measured surface area before adding allowance. Set the allowance to 0% if your entered quantity already includes the extra material.
“By area” adds the allowance to your measured area. “By carpet roll” uses the roll width and selected direction to estimate full-width strips, adding the allowance to each strip’s length. Enter outer dimensions where requested; both must fully contain the shape. Each area is estimated separately without reusing offcuts.
Open “Add costs (optional)” and select the price unit and currency. Enter carpet, underlay or fitting rates; leave unwanted costs blank. Carpet cost uses the estimated purchase area, underlay uses measured area plus allowance, and fitting uses measured area. Select “Calculate carpet” to review the quantities and any entered costs.
Compare an area estimate with a roll estimate for the same room, and see how the roll width affects the carpet quantity and material cost.
Enter these measurements and select each estimate type in turn. Roll width and direction apply only to “By carpet roll”. The price is illustrative; underlay and fitting prices are left blank.
Length × width = 15 × 10
This is the measured floor area before any cutting allowance or roll-width adjustment.
Add 10% to the measured area: 150 × 1.10 = 165 ft².
Carpet cost: 165 × USD 2.00 = USD 330.00.
This method adds 15 ft² for cutting allowance. It does not account for the available roll width.
Run the carpet along the room’s 15-foot length. The number of strips is 10 ÷ 12, rounded up to 1 full-width strip.
Add 10% to the strip length: 15 × 1.10 = 16.5 ft.
Roll quantity: 12 × 16.5 = 198 ft².
Carpet cost: 198 × USD 2.00 = USD 396.00.
Use your estimate as a starting point, then check these product and installation details before ordering carpet.
Check the available width of your chosen carpet with the supplier. Agree on pile direction and seam positions with your installer before choosing a cutting layout. The calculator estimates each area separately and does not plan seams or reuse offcuts between areas.
Patterned carpet may need extra length to align its repeat across adjoining pieces. Ask your installer how this affects the order. A percentage allowance does not calculate pattern repeats. Stairs, landings and shaped steps need their own measurements and cutting plan.
Confirm whether underlay is required and which type suits your carpet, installation method and subfloor. Check its roll or pack coverage separately. The underlay cost estimate uses measured area plus the selected cutting allowance; it does not round up to whole packs or include subfloor repairs.
Confirm the supplier’s minimum order and length increments. Ask whether the quote includes delivery, furniture moving, old carpet removal, trims, fitting and tax. Review these responsibilities using the installation preparation guidance. The calculator totals only entered prices, so compare quotes using the same included services.
Answers about carpet measurements, supported shapes and understanding your estimate.
Use decimal feet or select inches and enter the total number of inches. For example, 12 feet 6 inches is 12.5 feet or 150 inches. Do not enter 12.6 feet for this measurement. Changing the measurement unit converts existing dimensions, custom areas and roll width. Select “Calculate carpet” again after changing an input.
Divide the space into supported shapes that do not overlap and select “Add another area”. Alternatively, choose “Custom area” and enter an area you have already calculated. The pentagon and hexagon options apply only to regular shapes with equal sides and equal angles. In roll mode, enter outer dimensions where requested; both must fully contain the shape.
Measure the surfaces where carpet will actually be installed. Movable furniture does not usually change that coverage. Confirm with your installer whether fixed cupboards or other permanent fixtures should be excluded. You can enter the remaining measured area using “Custom area”. In roll mode, excluding a fixture may not reduce the full-width cut needed, so confirm the cutting plan before ordering.
No. Roll length is a linear measurement, while carpet area is roll width multiplied by that length. A 12-foot-wide roll cut to 16.5 feet contains 198 square feet. Match your quote to the selected area price unit; this calculator does not accept a price per linear foot or linear metre. For a practical explanation of roll width and room measurements, see this carpet measuring guide.
You can estimate coverage and an area-based carpet cost using “By area”, but this calculator does not count tiles or round purchases to full boxes. For square or rectangular carpet tiles, use the Tile Calculator with the tile dimensions, waste allowance and tiles per box.
The result shows a subtotal when only some of the carpet, underlay and fitting prices are entered. It shows an estimated total when all three are entered, including a zero price where appropriate. Neither label includes unentered charges such as delivery, removal or tax. Changing the price unit converts entered rates. Selecting a currency changes the currency label without applying an exchange rate.
Enter your measurements and choose an area or carpet roll estimate. Adjust the cutting allowance, then add optional carpet, underlay and fitting prices to plan your purchase.
Use the Carpet Calculator