Flooring Calculator — boxes for a floor

How it works

Laminate, vinyl plank and hardwood flooring are sold by the box, each covering a stated number of square feet. To find how many boxes to buy, take the floor area, add a waste allowance for cuts, and divide by the coverage per box:

boxes = ⌈area × (1 + waste) ÷ box coverage⌉

The coverage per box is printed on the carton (often 18–30 sq ft) and is an input here. A 10% waste allowance is standard for straight layouts; go to 15% for diagonal or herringbone patterns, or for rooms with lots of corners. The result rounds up to whole boxes.

Buying whole boxes and a little extra is wise — it lets you set aside a spare plank or two for future repairs, since dye lots change between production runs.

Worked example

A 200 sq ft room with a 10% waste allowance and 20 sq ft per box needs (200 × 1.1) ÷ 20 = 11 → 11 boxes. Choosing a larger 30 sq ft box drops it to ⌈220 ÷ 30⌉ = 8 boxes. Laying the same floor on the diagonal (15% waste) pushes it to ⌈230 ÷ 20⌉ = 12 boxes.

Frequently asked questions

How many boxes of flooring do I need?

Divide the floor area (plus a waste allowance) by the coverage per box and round up: boxes = ⌈area × (1 + waste) ÷ box coverage⌉. A 200 sq ft room at 20 sq ft/box with 10% waste needs 11 boxes.

How much flooring waste should I allow?

About 10% for a standard straight layout, covering cuts at walls and around obstacles. Diagonal, herringbone or chevron patterns waste more — allow 15% or even 20%. Long, simple rooms waste less; small, cut-up rooms waste more.

Why buy extra flooring?

Beyond covering cuts, keeping a spare box (or a few planks) lets you replace a damaged board later with an exact match. Dye and grain lots vary between production runs, so material bought now may not match a future purchase.

How do I find the floor area?

Multiply the room's length by its width. For irregular rooms, split them into rectangles, calculate each, and add. Measure into closets and doorways you plan to floor, and the calculator's waste allowance covers the trimming.

Does the coverage per box vary?

Yes — it depends on the product and plank size, typically 18 to 30 square feet per box. It is always printed on the carton. Enter that figure so the box count matches what you are actually buying.

What about underlayment and trim?

This sizes the flooring boxes only. Underlayment is calculated from the same floor area (usually sold in rolls), and trim like baseboards and transition strips is measured by length. Estimate those separately.