SuperDevTools
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Flooring calculator: laminate, hardwood and vinyl planks

Units

1. Room area

A rectangular room is one area. For an L-shaped room, a hallway or several rooms, add areas: they are added together.

    Areas to subtract

    Built-in closet, kitchen island, fireplace hearth, shower tray: their area is taken off.

      2. Planks and pattern

      Common practice: 5 to 8% for a straight lay (7% used here), 10 to 15% for a diagonal lay (12% used here), 15% for chevron or herringbone, where every plank is cut at the ends. You can enter your own figure.

      3. Boxes

      The box label shows its coverage in square feet or the number of planks. Leave it blank to skip the box count.

      4. Rows

      Rows are counted on area 1, for a straight lay. The expansion gap is taken off both sides before dividing by the plank width; 3/8 in (about 8 to 10 mm) is a common figure, but the installation guide of your flooring comes first.

      5. Underlayment, thresholds and baseboard

      One threshold (transition strip) is counted per doorway; doorway widths are taken off the baseboard length.

      With a single area, the perimeter is 2 × (length + width). With several areas, enter it yourself. 10% is added for corner cuts.

      6. Budget (optional)

      7. Result

      To buy, waste included —

      Step-by-step calculation

        Buy all the boxes at once, same product and same lot. Leave them closed and flat in the room for 48 hours before installing, so they adjust to its temperature and humidity.

        Your measurements and settings stay on this device and come back on your next visit. The copied link reopens the calculation with the same values.

        How much flooring do I need?

        This flooring calculator starts from the room size and the plank size. It adds the waste allowance that suits your layout pattern, then gives the number of planks, the number of boxes to buy and the square footage you actually order. It works for laminate, engineered wood, solid hardwood and click vinyl plank (LVP).

        It also counts the rows across the room after taking off the expansion gap on both sides, and warns you when the last row would be too narrow. Underlayment rolls, baseboard, thresholds and an optional budget are included.

        How to use it

        1. Keep Imperial (ft, in) or switch to Metric (m, mm), then enter the length and width of Area 1. For an L-shaped room or a hallway, click Add an area; take off a kitchen island or a built-in closet under Areas to subtract.
        2. Pick a Plank size or a Custom size, then a Layout pattern. The Waste allowance fills in by itself and you can change it.
        3. Copy the box label, as Coverage per box or Planks per box.
        4. Set the Plank direction and the Expansion gap at the wall, then the underlayment, doorways and baseboard. The Result and the step-by-step calculation update as you type.

        Worked example: a 16 × 12 ft living room

        Laminate planks of 50.59 × 7.56 in (1285 × 192 mm), boxes of 23.9 ft², straight lay with 7% waste, planks running along the 16 ft wall, 3/8 in expansion gap, one 3 ft doorway, 8 ft baseboard pieces, 100 ft² underlayment rolls.

        • Area: 16 × 12 = 192 ft².
        • One plank covers 50.59 × 7.56 in = 2.656 ft².
        • With waste: 192 × 1.07 = 205.44 ft², so 205.44 ÷ 2.656 = 77.35, rounded up to 78 planks.
        • Boxes: 205.44 ÷ 23.9 = 8.6, so 9 boxes, or 215.1 ft² ordered.
        • Rows: 144 − 2 × 3/8 = 143.25 in to cover; 143.25 ÷ 7.56 = 18.95, so 19 rows, the last one 7.17 in wide (95% of a plank).
        • Underlayment with 5% overlap: 192 × 1.05 = 201.6 ft², so 3 rolls of 100 ft².
        • Baseboard: 2 × (16 + 12) = 56 ft, minus 3 ft of doorway = 53 ft, plus 10% = 58.3 ft, so 7.29, rounded up to 8 pieces; plus 1 threshold.

        At $3.50 per ft², the flooring comes to 215.1 × 3.50 = $752.85. With a Diagonal lay, waste rises to 12%: 215.04 ft², still 9 boxes, with almost nothing to spare. In metric, a 5 × 4 m room with 2.22 m² packs needs 21.4 m², so 10 packs.

        When the last row is too narrow

        In a room 11.5 ft wide with the same planks, 137.25 ÷ 7.56 = 18.15: the last row would be only 1.17 in wide. A strip that thin snaps when you click it in and looks wrong against the wall. The tool then shows a warning and suggests ripping the first row so that the first and last rows are both (1.17 + 7.56) ÷ 2 = 4.37 in. You buy the same amount of flooring.

        Before you install

        • Acclimation: leave the boxes closed and flat in the room for 48 hours so the planks adjust to its temperature and humidity.
        • Direction: planks usually run parallel to the light from the main window, which hides the seams, or along the length of a hallway.
        • Stagger the end joints by at least 12 in from one row to the next, and start each row with the offcut from the previous one.
        • Check that every box comes from the same lot.

        Frequently asked questions

        How much extra flooring should I buy?

        Common practice is 5 to 8% for a straight lay, 10 to 15% for a diagonal lay and about 15% for chevron or herringbone. The tool uses 7%, 12% and 15%; a room with many corners deserves a little more.

        How do I work out boxes of laminate?

        Multiply the area by 1 plus the waste, divide by the coverage of one box and round up. For 192 ft² at 7% with 23.9 ft² boxes: 205.44 ÷ 23.9 = 8.6, so 9 boxes.

        Does the expansion gap change the amount to buy?

        Not really: a few fractions of an inch along the walls do not change the box count. It does change the rows, which is why the tool takes it off both sides before dividing by the plank width.

        Do I need underlayment for vinyl plank?

        Many click vinyl planks come with an attached pad. In that case, untick Count underlayment and follow the installation guide.