Flooring Calculator

How much flooring do I need?

Stores sell flooring by the box, but you measure a room in length and width, so every order needs a conversion. Multiply length by width for the floor area, add a waste allowance for cut-offs and mistakes, then divide by the coverage printed on the carton of the laminate, vinyl, vinyl plank, or hardwood you have picked. Whatever fraction is left over gets rounded up: the store will not split a carton, so 6.6 boxes on paper is 7 at the register.

The answer you need at the counter is the box count, which is why it is the headline result above. The two figures under it show how much floor the order has to cover once waste is added and how much it will actually cover once rounded up to whole cartons. The gap between them is your built-in margin.

Formula & methodology

Area = Length × Width. A waste/cut allowance (10% by default) goes on top, since real installs lose material to trimming the last row, cutting around door casings, and staggering end joints. Boxes needed = area with waste ÷ coverage per box, rounded up to the next whole number. Total coverage = boxes × coverage per box, which is usually a little more than the area with waste.

The material dropdown labels your estimate but does not change the arithmetic; coverage per box already captures the difference between products. In metric mode, length and width are in meters and coverage in m², the unit most packs sold outside the US print. Switching units converts the numbers you have entered (1 ft = 0.3048 m; 1 m² = 10.764 sq ft). For a one-off conversion of a label figure, use the square feet to square meters converter.

Worked example: a 14 × 11.5 ft bedroom

Say you are laying 12 mm laminate sold at 19.63 sq ft per case, planks run straight, with a 10% allowance.

1. Room area: 14 ft × 11.5 ft = 161 sq ft.
2. Add 10% waste: 161 × 1.10 = 177.1 sq ft.
3. Divide by the case coverage: 177.1 ÷ 19.63 = 9.02 cases.
4. Round up: 10 cases, which cover 196.3 sq ft.

That 9.02 is the trap: being 0.02 of a case short means the tenth carton is needed for a sliver of floor, and you end up with roughly 19 sq ft of margin beyond the waste allowance. Before accepting it, re-measure. If the room is actually 13 ft 10 in long, the order drops to 9 cases.

How to measure a room for flooring

• Measure the longest length and width of the room wall to wall, in feet or meters, at floor level rather than across the top of baseboards.
• Include closets, alcoves, and the floor under door openings where the new floor will run to a threshold.
• Leave out the footprint of fixed kitchen cabinets and islands if your floating floor will stop at their base.
• For an L-shaped or irregular room, split it into rectangles and add them up; the square footage calculator for L-shaped and multi-room areas does that sum, and you can enter the total here as a single length × width (for example 1 × 186).
• Measure twice, ideally on different days. Every box count is only as good as the tape reading behind it.

Coverage per box & boxes by room size

Coverage per carton depends on plank size and pieces per box, so there is no standard figure. The examples below come from US retail product listings (Home Depot, checked October 2026) to show the typical spread; the number on your own label is the one to use.

So most plank cartons land somewhere around 14–25 sq ft, and the same brand can vary by almost half between a narrow and a wide plank. The next table shows how that plays out in common rooms, computed with this page’s formula at a 10% waste allowance.

Two rows sit right on the edge: 12 × 12 ft with 20 sq ft boxes leaves only 1.6 sq ft beyond the allowance, and 15 × 20 ft with 30 sq ft boxes leaves none. Treat those as a nudge to add a box.

Waste allowance by layout

How much extra to add depends mostly on the cutting pattern. These are common installer rules of thumb, not manufacturer specs; your installer may ask for more on a difficult room.

• Straight lay, simple rectangle: 5–10%. The cut end of each row usually starts the next one, so little is thrown away.
• Many corners, closets, or doorways: around 10–15%. Each notch and jamb undercut produces short offcuts.
• Diagonal or herringbone: about 15%, sometimes more. Every perimeter piece is an angled cut, and the triangles left over rarely fit elsewhere.

On a 12 × 12 ft room with 20 sq ft boxes, going from 10% to 15% raises the order from 8 to 9 boxes. Laying porcelain or ceramic instead of planks? The tile calculator counts individual tiles, grout, and thinset.

What flooring costs

Laminate and luxury vinyl plank typically run roughly $4–$10 per sq ft installed, materials plus professional labor (rough 2026 US range; prices vary by region — get local quotes). For a 12 × 10 ft room of 120 sq ft, that is about $480–$1,200. Installers usually price on the room area, while your material bill follows the rounded-up box count, so check which figure a quote is based on. Solid hardwood, subfloor repairs, removing old flooring, and moving furniture all add to the total; ask for them as separate line items.

Tips for ordering flooring

• Use the coverage figure on the exact product and plank width you are buying; even within one brand it can range from under 14 to over 22 sq ft per case.
• If your count lands just past a whole number (like 9.02), re-measure before paying for the extra carton; if it lands just under one, treat the next carton as cheap insurance.
• Check that every carton carries the same lot or run number and keep one unopened afterwards; matching a discontinued color for a repair years later is often impossible.
• Let boxes acclimate in the room for as long as the manufacturer’s instructions say before installing, especially for hardwood and laminate.
• Buying outside the US? Switch to metric mode and enter the m² per pack from the label; packs are sized differently from US cases, so don’t reuse a US coverage figure.