Carpet Calculator

Carpet square footage formula

For a rectangular room, measured area is room length multiplied by room width. Any entered waste allowance is applied after the measured area is calculated.

purchase area = room length × room width × (1 + waste %)

The calculator also converts the purchase area into square yards by dividing square feet by nine.

Why carpet orders can require more than room area

Carpet is commonly supplied in rolls, so the most efficient seam layout may not match a simple room-area calculation. Roll width, pattern direction, pattern repeat, closets, alcoves, stairs and installer seam rules can all increase the real amount purchased.

Use this tool as an area and cost-planning check, then compare the result with the exact roll width and layout used by the retailer or installer.

Optional budget check

The calculator can still accept optional material or labor prices as a quick planning check, but the primary intent of this page is carpet quantity. For a dedicated budget workflow with fixed extras and a separate cost-focused search intent, use the Carpet Cost Calculator.

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Carpet roll width and linear feet

When you enter the actual product roll width, the calculator tests two simple rectangular layouts: full-width strips running along the room length and full-width strips running along the room width. It shows the orientation with the lower linear roll requirement.

strips = ceil(room span ÷ roll width)
linear roll length = strips × run length
roll area purchased = linear roll length × roll width

This simple roll comparison does not infer pile direction, pattern repeat, trim allowance, closets, stairs or installer seam rules. Confirm those details against the exact carpet and installation plan before ordering. For budgeting, carry the measured area into the Carpet Cost Calculator and use current local quotes.

Example: two orientations with a 12-foot-wide roll

A rectangular room measuring 10 × 14 ft has a floor area of 140 sq ft, but a 12 ft wide carpet roll may require purchasing more. If a full 12 ft width runs along the 14 ft room length, one 14-linear-ft cut buys 168 sq ft of carpet. If the cut runs along the 10 ft room length, covering 14 ft across the roll width requires two strips of 10 ft, or 20 linear ft of a 12 ft wide roll: 240 sq ft.

The apparent material saving from the first orientation is meaningful only if the carpet's pile direction, pattern and seam plan permit that layout. Stairs, alcoves and manufacturer rules can add further material. Enter the actual product width in the calculator and use the retailer's seam plan to confirm the order.