Flooring
calculator.
Enter the room size or total area, a waste allowance and the coverage printed on the box to see how many boxes of laminate, vinyl plank or hardwood to buy. For carpet, it lays full-width strips on the roll and gives the square yards and seams.
For 180 sq ft of laminate with 10% waste, buy 10 boxes (200 sq ft) for about $600.00.
- Boxes to buy
- 10 boxes
- Floor area
- 180 sq ft
- With 10% waste
- 198 sq ft
- Flooring in 10 boxes
- 200 sq ft
- Beyond the floor area (waste + spare)
- 20 sq ft
- Material cost
- $600.00
A = 15 ft × 12 ft = 180 sq ft; 180 × (1 + 10%) = 198 sq ft; 198 ÷ 20 = 9.9 → 10 boxesArea, plus waste,
in whole boxes.
- Material needed = floor area × (1 + waste % ÷ 100). The waste allowance is your choice; manufacturers suggest about 5–10% for a regular room and more for diagonal layouts or awkward rooms.
- Boxes = material needed ÷ coverage per box, always rounded up to a whole box. A result that is exactly whole, such as 10.0, is not rounded up again.
- Hard-floor cost is the price per square foot (or m²) times the flooring in the boxes you buy, or the price per box times the boxes.
- Carpet with length × width uses full-width strips all running the same way: strips = room width ÷ roll width, rounded up, each cut to the room length plus the allowance. Both directions are tried and the smaller purchase is shown. Carpet is priced per square yard (9 sq ft), or per m² in metric.
How do you calculate how much flooring you need?
Multiply the room's length by its width, add the waste allowance, and divide by the coverage per box. A 15 by 12 ft room is 180 sq ft. With 10% waste that is 180 × 1.10 = 198 sq ft. Boxes that cover 20 sq ft each give 198 ÷ 20 = 9.9, so you buy 10 boxes, or 200 sq ft. At $3.00 per sq ft the material costs $600.00.
material = area × (1 + waste ÷ 100)
boxes = ⌈material ÷ coverage per box⌉How much extra flooring should I buy for waste?
Manufacturers give similar starting points. Quick-Step and Pergo both say a regular room needs about 5% extra and a room with many angles or curves about 10%. Bruce calls 10% the usual starting point for a straightforward plank layout and says diagonal installations, busy patterns, stairs and irregular rooms need more. Mannington says a waste factor of 5–15% is added depending on the product. Check the installation guide for your product, because it is the most specific source.
How many boxes of flooring do I need?
Divide the area with waste by the square feet in one box, and round up. Flooring is sold by the box, so 7.12 boxes means 8. A 13 ft 6 in by 11 ft 9 in room is 13.5 × 11.75 = 158.625 sq ft; with 5% waste that is 166.56 sq ft, and boxes of 23.4 sq ft give 7.12, so buy 8 boxes. The coverage per box is printed on the carton and the product page and differs between products.
How do you calculate carpet in square yards?
Divide square feet by 9. A 15 by 12 ft room with a 10% allowance is 198 sq ft, or 22 sq yd. Carpet comes on rolls of a fixed width, though, often 12 ft, and you pay for the full width you cut. A 14 by 14 ft room is 196 sq ft of floor, but on a 12 ft roll it takes two 14 ft strips laid the same way: 2 × 14 × 12 = 336 sq ft, or 37.33 sq yd, with one seam. The leftover strip may cover a closet.
strips = ⌈room width ÷ roll width⌉
carpet = strips × length × (1 + allowance) × roll width
square yd = square feet ÷ 9Does the flooring cost include installation?
No. The cost here is the flooring material only, for the whole boxes or carpet you buy. Underlayment, padding, transition strips, trim, adhesive and labor are extra. Bruce advises keeping one unopened carton after the install if you have space, because a later batch may not match for repairs.
Worked examples.
Laminate for a bedroom
A 15 by 12 ft room, 10% waste, boxes of 20 sq ft at $3.00 per sq ft.
10 boxes (200 sq ft), about $600.00.
Load this exampleVinyl plank in feet and inches
A 13 ft 6 in by 11 ft 9 in kitchen, 5% waste, boxes of 23.4 sq ft at $52.00 a box.
8 boxes (187.2 sq ft), about $416.00.
Load this exampleHardwood laid on a diagonal
450 sq ft across several rooms, 15% waste for a diagonal layout, boxes of 18.5 sq ft.
28 boxes (518 sq ft).
Load this exampleLaminate in meters
A room 4 m 50 cm by 3 m 20 cm, 7% waste, packs of 1.86 m² at €14.90 per m².
9 boxes (16.74 m²), about €249.43.
Load this exampleCarpet on a 12 ft roll
A 14 by 14 ft room on a 12 ft roll, no extra allowance, at $30.00 per sq yd.
37.33 sq yd in two strips with one seam, about $1,120.00.
Load this exampleCarpet by total area
180 sq ft of floor with a 10% allowance at $54.00 per sq yd.
22 sq yd, about $1,188.00.
Load this exampleWhat this calculator
does not do.
- Waste depends on the room, the layout and the product. The allowance is your estimate; the calculator does not plan the cuts.
- The carpet layout uses full-width strips in one direction. It does not plan cross-pieces, pattern repeats or stairs.
- Costs cover the flooring only, not underlayment, padding, trim, adhesive, delivery, tax or labor.
- It does not check subfloor, moisture or acclimation requirements. Follow the manufacturer's installation instructions.
Common questions.
How many boxes of flooring do I need for a 12 by 12 room?
144 sq ft plus 10% waste is 158.4 sq ft. With boxes of 20 sq ft that is 7.92, so 8 boxes. With 22 sq ft boxes it is 7.2, also 8 boxes.
Should I round up to a full box?
Yes. Flooring is sold by the box, so any fraction means one more box. The calculator always rounds up, but it does not add a box when the result is already whole.
How many square feet are in a square yard of carpet?
Nine: a square yard is 3 ft by 3 ft. Divide square feet by 9 to get square yards.
What waste factor should I use for a diagonal or herringbone floor?
More than for a straight layout. Bruce says diagonal installations and busy patterns need more than its usual 10%. Use the figure in your product's installation guide.
Can I add several rooms?
Yes. Choose Total area and enter the sum of the rooms' areas. Subtract fixed cabinets and islands first.
- Quick-Step: How much floor do I need for my room? — 5% extra for a regular room, 10% for rooms with many angles or curves
- Pergo: How much flooring is required for my space? — 5% for a standard-sized room, 10% for a small room with tricky areas
- Bruce: How to Buy Flooring, a guide for homeowners — priced by the square foot, sold by the carton; 10% starting point; diagonal and irregular rooms need more
- Mannington: What to expect from your floor installation — a 5–15% waste factor depending on the product
- NIST Handbook 44 (2026), Appendix C: General Tables of Units of Measurement — 1 sq yd = 9 sq ft; 1 ft = 0.3048 m exactly
The floor area comes from length × width (feet plus inches, or meters plus centimeters) or from the total you enter. The waste allowance is applied, and boxes are rounded up with a guard so that floating-point noise never adds a box to an exact fit. Carpet strips are laid both ways on the roll and the smaller purchase is kept. Tests cover hand-worked vectors, 400 random cases checking that the boxes cover the need and one fewer would not, unit equivalence between feet and meters, roll layouts, and every input error.
Built and reviewed by CalculatorLab against the sources above; every worked example on this page is re-checked by our automated test suite before each release. How we build and check calculators. Found a problem? Tell us.