Flooring Calculator — ft, sqft to boxes, planks, cost
How to use this calculator
Enter room dimensions in feet, inches, and fractions, or switch to the L-shape or direct-area tab. Pick the flooring type, plank size, install pattern and waste allowance — the box count, plank count, underlayment rolls and transition strips recalculate as you type.
Flooring types — Laminate, Engineered hardwood, Solid hardwood, Vinyl plank (LVP), Bamboo.
Box coverage — typically ~20 ft²/box, adjustable.
Underlayment — rolls at 100 ft²/roll.
Transition strips — T-molding, reducer, end cap for doorways.
Saved Calculations
| Time | Shape | Area ft² | Type | Boxes | Planks | Underlay | Trans. | Total |
|---|
How to Calculate Flooring Boxes
Floor area is measured net of the room footprint, then inflated by a waste factor before being divided by the labelled box coverage. The result is rounded up to whole boxes because flooring is sold only by the unopened box. For L-shaped rooms, enter the full A×B rectangle and subtract the C×D notch. If you already know the square footage, use the Area tab. After estimating boxes, plan the perimeter with the paint calculator for baseboards and the drywall calculator if walls are being redone first.
Formulas
Net area A = L × W (rectangle) or A·B − C·D (L-shape). Boxes = ⌈A·(1+w) ÷ C_box⌉ where w is the waste fraction and C_box the box coverage in ft². Planks per box ≈ C_box ÷ (plank_w·plank_l ÷ 144), with plank dimensions in inches. Underlayment rolls = ⌈A·1.05 ÷ 100⌉ at 100 ft²/roll including a 5% overlap.
Waste and Box Coverage
Use 5% for a plain rectangle with straight planks, 10% for a typical room with a few cuts, and 15% for diagonal or herringbone layouts and rooms with many doorways or jogs. Box coverage varies by product — most laminate and LVP boxes cover 18–24 ft²; always confirm against the product label and adjust the field. Stagger end joints at least 6 inches and leave a 1/4-inch expansion gap at every wall.
Underlayment and Transitions
Foam or felt underlayment is required for laminate on concrete subfloors and recommended for all floating installations; standard rolls cover 100 ft² with a built-in moisture barrier and 6-inch seam overlap. T-molding joins two same-height floors, a reducer bridges to a thinner surface, and an end cap finishes an exposed edge — count one strip per doorway or transition. For wall-to-wall carpet instead of planks, switch to the carpet calculator, or compare a tiled floor with the tile & grout calculator.
On install day
Three things estimators miss on flooring takeoffs. Acclimation — solid and engineered wood need 48–72 hours in the room at 60–80 °F and 30–50% RH before opening boxes (NWFA §6.1); skip this and the planks cup or gap in the first heating season. Cuts at doorways and closets — narrow returns waste a full board, so bump waste from 10% to 12–15% when the room has many jogs or you're running diagonal. 2025 material pricing: laminate $1.50–3/ft², LVP $2–5/ft², engineered $4–9/ft², solid hardwood $6–12/ft², bamboo $3–6/ft²; add $3–6/ft² installed labor. Always order one extra box for attic stock — discontinued runs make future patch repairs impossible.
FAQ
Why round up to whole boxes? Retailers sell flooring by the sealed box; partial boxes are not available, and keeping one spare board from a full box helps with future repairs.
Do staggered and random patterns use more material? No — the area is identical. They change the cutting sequence and offcut reuse, which is why higher-cut layouts get a larger waste allowance.
Does the plank count change the number of boxes? No. Boxes are driven by area and box coverage; the plank count is informational, derived from the plank size you select.
