Carpet flooring calculator.
Order the roll length the seams require.
Broadloom comes off a roll of fixed width, so a room is covered by full-width drops plus a fill strip pieced from extra roll length. This calculator lays both, tries each allowed number of T-seams in the fill, compares both pile directions and reports linear feet, square yards and the offcuts that the roll width forces.
02 / Seam plan
03 / Order
- Purchased
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- Purchased area
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- Room area
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- Waste ratio
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- Seams
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- Cuts from the roll
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- Longest cut
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- Area-only estimate
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Linear length is what the dealer cuts. The area-only row shows what a flat percentage would order instead.
Both pile directions, side by side
| Pile | Drops | Fill width | Seams | Linear | Purchased | Waste | Longest cut | Select |
|---|
Fill strip: every allowed number of pieces
| Fill | T-seams | Piece length | Per cut | Cuts | Roll added | Spare pieces |
|---|
When the fill is narrow, several pieces fit across one cut and every T-seam shortens the order. When it is wide, only one piece fits per cut and more pieces mean more cuts, so the table can turn upward again.
Roll cut sheet and pieces
| Piece | Kind | Laid size | Cut length | Roll from–to | From roll edge |
|---|
Cuts and offcuts
| Cut | Length | Pieces | Width used | Offcut |
|---|
Why a 14-foot room on a 12-foot roll needs 19 feet 2 inches
The example room is 14 feet wide and 16 feet long. Laid with the pile along the 14-foot width, one drop 12 feet wide covers 12 of the 16 feet of length, cut 14 feet 3 inches long with the 3-inch margin. The remaining 4-foot strip runs the full 14 feet. As one piece it would need another 14 feet 3 inches of roll for 4 feet of width, leaving 8 feet of width as offcut. Cut in three pieces of 4 feet 11 inches, side by side across one cut, the fill adds only 4 feet 11 inches to the order: 19 feet 2 inches in total, 230 square feet for a 224-square-foot room, 2.7 percent waste. A fourth piece would not fit across the roll and would need a second cut.
Laid the other way, with the pile along the 16-foot length, the drop is cut 16 feet 3 inches and the fill is only 2 feet wide, so six pieces could sit across one cut; with two T-seams allowed, three pieces of 5 feet 7 inches give 21 feet 10 inches in total. The direction table shows both before a yard is cut.
Where a flat percentage goes wrong twice
A 12-by-15 room is one drop cut 15 feet 3 inches: 183 square feet, 1.7 percent over the room. An estimator adding 10 percent orders 198 square feet, 16.5 linear feet, a foot and a quarter too much. A 14-by-22 room needs a 12-foot drop and a 10-foot fill, each 14 feet 3 inches: 28 feet 6 inches, 342 square feet, 11 percent over the room; the same estimator orders 338.8 square feet and comes up short. The percentage is not wrong by a constant; it is wrong by whatever the roll width decides.
What ranking calculators multiply
| Calculator | Basis observed | Inputs | Outputs |
|---|---|---|---|
| MeasureSquare carpet calculator | drops and fill pieces cut from a 12 ft roll with a 3 in margin, T-seams allowed in the fill, layout image and cut sheet rendered before the optional email | 12 × 15 ft; 14 × 16 ft; 14 × 22 ft (rectangle, defaults) | 15′3″ linear, 183 SF, 20.33 SY, 1.6 % waste; 19′2″ linear (12×14′3″ drop + three 4′11″ fill pieces), 230 SF, 25.56 SY, 2.6 %; 28′6″ linear (12×14′3″ + 10×14′3″), 342 SF, 38.00 SY, 9.9 % |
| Godfrey Hirst floor calculator (North America) | square feet plus a wastage percentage (default 10), square yards; note states 3.66 m width for lineal calculations | 12 × 15 ft carpet | 180.00 sub total, 18.00 wastage, 198.00 ft², 21.78 yd² |
| The Perfect Carpet calculator | rooms and staircases → square feet, 10 % waste, linear roll length = area with waste ÷ roll width | 12 × 15 ft, 0 staircases | 180.00 sq ft, waste 18.00, 198.00 sq ft; linear length 16.50 ft at 12 ft, 15.23 ft at 13 ft, 13.20 ft at 15 ft width |
| Omni Calculator carpet | shape → area × price | rectangle 12 × 15 (metres by default) | 180 m² area; cost field multiplies by price |
| S&G Carpet and More calculator | rooms in feet or inches, optional price; page states 10 % waste; results behind a form submit | page read | totals not captured; 10 % waste rule recorded from the page |
| Carpet Guys square foot calculator | rooms in feet and inches, rounded up to the inch, total square feet × price per square foot | 12 × 15 ft | form submitted; totals not captured by the test browser |
| Lowe's carpet measurement calculator | not executed: lowes.com answered Access Denied to the test environment on 2026-09-10 | none | none |
MeasureSquare lays out seams correctly and its three rooms were reproduced here to the inch, which is the check that this engine is right. It prints the chosen layout only, and states waste as a share of the purchase where this page states it as a share of the room, so its 9.9 percent and the 11 percent above describe the same 34 square feet. The other estimators multiply area by a percentage, and one of them divides that by the roll width and calls it linear feet.
Cut margin, repeat and roll length
The margin is added to every cut, drops and fill pieces alike. A pattern repeat rounds each cut up to whole repeats so seams can be matched; the extra length shows in the cut table and the balance line, not inside a percentage. If the dealer’s roll has a known usable length, enter it and the page warns when a single cut exceeds it, because a room longer than the roll needs a cross seam this model does not plan.
Every piece carries its position on the roll, from and to, and its offset from the roll edge, so the cut sheet can be handed over as it is. Offcuts are listed with both dimensions; whether one becomes a closet or a stair piece is a decision for the installer, not an allowance the page takes. Rigid plank floors are planned in the plank row planner; roll underlay beneath laminate has its own strip schedule.
Questions before the roll is cut
How do I calculate how much carpet a room needs?
Enter the room and the roll width. Drops of full roll width run along one direction; what is left across the room is a fill strip cut across the roll in pieces, each with its pile the same way. The order is the sum of the cut lengths in linear feet, not the room area plus a percentage.
How many yards of carpet does a 10-by-10 room take?
On a 12-foot roll a 10-by-10 room is one drop cut 10 feet 3 inches long with a 3-inch margin: 123 square feet or 13.67 square yards ordered for 100 square feet laid, the 2-foot strip along the roll being offcut. Square yards here are purchased area, roll width times linear length, divided by nine.
What does carpeting a 20-by-20 room cost?
Price is not on this page, but the quantity is: on a 12-foot roll a 20-by-20 room takes one drop and an 8-foot fill, and the fill table shows how many linear feet each T-seam option saves. Multiply the linear feet by the quote per linear foot, or the square yards by the quote per yard, and add pad and labor separately.
What would 1,000 square feet of carpet cost?
A thousand square feet spans several rooms with their own seams, and the linear feet of each room depend on its shape against the roll width. Run each room here, add the linear feet, then apply your dealer’s price. A flat percentage on the total area misses the fill strips entirely.
Does the calculator work in square feet?
The ledger prints square feet laid, square feet purchased and square yards, with the linear feet that produced them. The purchased figure equals roll width times linear length; the difference from the laid area is itemized as cut margins and offcuts in the balance line.
Can I use square metres and a 4-metre roll?
Switch to metric. Room, roll width, margin and repeat are entered in millimetres, results in metres and square metres. European broadloom is often 4 or 5 metres wide; enter the width on the sample label rather than a converted 12-foot figure.
Is this a free carpet measuring calculator?
Yes. The seam plan, roll cut sheet, piece list and CSV are available without an email or account. The preloaded 14-by-16-foot room, 12-foot roll, 3-inch margin and two allowed T-seams are example values, not a product.
Why is the order longer than the room area suggests?
Because a roll is a fixed width. A 14-foot-wide room on a 12-foot roll needs a 2-foot fill along its whole length, and that fill comes from extra roll length. Cut margins and pattern repeats add to every cut. The area-only row in the ledger shows what a flat percentage would have ordered instead.
Which unit should a carpet quote use?
Dealers quote by the square yard, square foot or linear foot of roll. All three are printed for the same plan, so the quote can be checked in the unit the dealer used. Linear feet are the least ambiguous, because they name the roll length actually cut.
Can I take this to Home Depot or Lowe’s?
Take the linear feet, the roll width and the cut list. Their estimators start from area and add a percentage; this plan shows the seams that the roll width forces. Ask the store which roll widths the chosen style is stocked in and rerun the plan for that width.
Does it handle stairs?
Not yet. Stairs are a run of tread-plus-riser pieces cut with the pile facing down the flight, and their count depends on the number of steps and any landing. Plan them as a separate order; this page covers one rectangular room.
Is there an app or a way to save the plan?
The calculator runs in the browser and nothing is stored on a server. Print the page, download the CSV of pieces, cuts and seams, or export the seam plan as SVG before leaving. The layout can be re-entered on a phone at the store.
What this seam plan leaves to the installer
- One rectangle, one roll width, one fill strip. No L-shapes, closets, stairs, landings or two rooms sharing a cut.
- Fill pieces are placed in one row along the fill; the model does not stagger T-seams away from doorways or traffic lines.
- Cut margin and repeat are your inputs; the 3-inch and 12-foot defaults are what ranking tools showed, not a rule.
- No padding, tack strip, seam tape, adhesive or labor quantities. No prices.
- Pile direction is assumed consistent for every piece; reversed pieces are not offered even where the material would allow it.