How flooring calculator works
Flooring is bought two ways at once: individual planks and sealed boxes, and the box is what the checkout asks for. Enter the room’s floor area and the plank dimensions; the calculator converts the plank size into its coverage, divides the room area by it, and rounds up to a whole plank count.
Raw plank counts underbuy. Every row ends in a cut, a few planks arrive warped, and mistakes happen with a utility knife — so the count is multiplied by a waste factor (10% is the straight-layout default) and rounded up again. Diagonal, herringbone, or staggered layouts cut more aggressively and deserve 15% or more.
If you enter the box coverage printed on the carton (say 23.8 sq ft), the plank count converts into boxes to buy plus the leftover coverage a full carton leaves. Keeping one unopened box is cheap insurance: manufacturers discontinue products, and a future dye lot rarely matches the floor you walked on all winter.