Flooring Calculator

Find how much flooring you need — enter your room size, the coverage per box and a waste allowance to get the square footage and number of boxes of laminate, vinyl or hardwood.

How much flooring do I need?

Flooring is sold by the box, each covering a set number of square feet. Measure the room’s area, add a waste allowance for cuts and mistakes, then divide by the coverage on the box. The calculator above rounds up to whole boxes so you buy enough — with a little spare for repairs.

boxes = area × (1 + waste%) ÷ coverage per box

Flooring waste by layout

LayoutWaste to add
Straight, simple room8–10%
Diagonal15%
Herringbone / patterned15–20%
Many cuts / angled room15%+

Most floating floors need an underlayment sized to the same area. For tile instead, use the tile calculator; for walls, the paint and drywall calculators.

Frequently asked questions

How much flooring do I need?

Measure the room’s square footage (length × width), add a waste allowance, then divide by the square feet each box covers. The calculator above does this and rounds up to whole boxes, so you walk out of the store with the right amount.

How much extra flooring should I buy for waste?

Add about 8–10% for a standard straight installation, and 15% or more for diagonal layouts, busy rooms with lots of cuts, or patterned planks. Keeping a spare box or two also helps for future repairs. The calculator defaults to 10%.

How many square feet are in a box of laminate?

It depends on the product, but a box of laminate or vinyl plank commonly covers around 18–24 square feet. Hardwood boxes are often around 20 square feet. Check the box label and enter that coverage above for an exact box count.

Do I need underlayment under flooring?

Most floating floors — laminate and many vinyl planks — need an underlayment for cushioning, sound and moisture, unless the planks have it pre-attached. Underlayment is sold by the roll in square feet, so size it to the same room area as the flooring.

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