Roll width + cuts + square yards
Carpet Calculator
Estimate how much broadloom carpet to buy for one or more rooms. See how roll width affects cut length, seams, and material cost.
Example only
- Floor area
- 120 sq ft
- 12 ft roll
- 13 linear ft
- Seams
- 0
With a 6 in trimming allowance and no additional percentage. Your estimate uses your measurements.
The math
Roll width changes the amount to buy
Square footage tells you the floor size. A carpet order also depends on how many full-width pieces must be cut from the roll.
Example: a 10 × 12 ft room, using a 12 ft roll
- Measured floor: 10 × 12 = 120 sq ft.
- Allow 6 in total on each room dimension for trimming.
- A single 12 ft wide piece can run across the 10 ft dimension; cut 12.5 ft from the roll.
- Round to 13 linear ft to order: 12 × 13 = 156 sq ft, or 17.33 sq yd.
Cut direction is an estimate. Pattern alignment, pile direction, room shapes, seams, and installer decisions can change the final order.
Measuring guide
Sketch rooms before you order
Measure each room
Record the longest length and width, including alcoves. Add a closet as a separate room.
Confirm roll width
Many broadloom products come in 12 ft or 15 ft widths; enter the width of your chosen carpet.
Review seams
Ask your installer to check the layout, pile direction, and any pattern repeat before ordering.
FAQ
Carpet calculator questions
How many square yards of carpet do I need?
Measure each room, then account for the available roll width and full-length pieces. This calculator estimates a cut layout and converts the resulting roll area from square feet to square yards by dividing by 9.
Why is the carpet purchase area larger than the floor area?
A fixed-width roll can leave wide offcuts, especially when a room is just wider than the roll. Trimming and any extra allowance also increase the order length.
What is a carpet seam?
When one roll-width piece cannot cover a room, additional pieces must be joined. This estimate counts one seam for every extra piece within a rectangular room; the installer chooses the final seam placement.
Does this include carpet padding?
The result shows the measured floor area in square yards as a starting pad quantity. Padding waste, packaging, stairs, and closets not entered in the form are not included.
Can I use this for carpet tiles or stairs?
For carpet tiles sold by box, use the Flooring Calculator. Stair layouts need tread, riser, width, and installation details, so this room-based broadloom estimate does not cover stairs.
References
Sources behind this calculator
Use the selected carpet’s specifications and have an installer confirm the cut plan.
Roll widths
The Carpet and Rug Institute lists common broadloom widths, including 12 ft and 15 ft.
Carpet and Rug Institute ↗Trimming and seams
Lowe’s installation guide allows 3 in at each edge and explains pile direction at seams.
Lowe’s installation guide ↗Final measurement
Lowe’s carpet guide cautions that wider rooms can need extra material to accommodate seams.
Lowe’s carpet planner ↗More tools