Flooring Calculator — Area, Boxes & Cost
Estimate how much flooring to buy: enter room dimensions, choose a waste allowance, and get the area with waste, box count, and total cost.
ft
ft
%
$/ft²
ft²/box
Room area plus waste allowance
- 1
Room area
15 × 12 = 180 ft² - 2
Waste multiplier
1 + 10 ÷ 100 = 1.1 - 3
Flooring needed
180 × 1.1 = 198 ft²
How does this calculator work?
Multiply room length by width to get area, then multiply by (1 + waste %) — typically 1.10 for straight-lay rooms. Divide by the per-box coverage and round up for box count. Multiply total area by price per sq ft for material cost. Ten percent waste suits most simple rectangular rooms.
Formula
How this is calculated
Flooring is sold by the square foot — or in boxes each covering a fixed area. The room area is simply length × width. A waste allowance accounts for cuts at edges, pattern matching, and unusable off-cuts: 10 % suits straight-laid planks in a simple rectangle; 15 % is standard for diagonal installation or rooms with multiple alcoves; 20 %+ for small mosaic tiles or intricate patterns.
Divide the total area (room plus waste) by the coverage per box from the product label, then round up to the nearest whole box — you must buy complete boxes. Total cost multiplies the total square footage by your price per square foot. If you only have a box price, divide it by the per-box coverage to get the per-sq-ft figure first.
This calculator assumes a single rectangular room measured wall-to-wall. Subtract built-in cabinets, islands, or hearths from the input dimensions before running the calculation. Thresholds, transitions, underlayment, adhesive, and installation labour are separate costs not included here.
Frequently asked questions
Standard practice is 10 % for a simple straight-lay room with minimal cuts. Use 15 % for diagonal installation or rooms with many corners, and 20 % or more for very small tiles or oddly shaped rooms. Buying a little extra also gives you spare planks for future repairs from the same lot.
Rounding up to whole boxes and the waste allowance both contribute to surplus. Store leftover planks — a few matching pieces from the same batch can save you from a colour-mismatch problem if you ever need to repair a damaged section.
Yes — the area and box math is the same for any flooring type. Enter the correct per-box coverage from the packaging (laminate boxes typically cover 18–22 ft²; tile varies widely). Installation method and cost differ by material but the quantity calculation is identical.
Also known as
TG we-Calculate Editorial Team. (2026). Flooring Calculator — Area, Boxes & Cost [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/flooring-calculator
TG we-Calculate Editorial Team. "Flooring Calculator — Area, Boxes & Cost." TG we-Calculate. 2026. https://we-calculate.com/calculator/flooring-calculator.
TG we-Calculate Editorial Team, "Flooring Calculator — Area, Boxes & Cost," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/flooring-calculator
@misc{wecalculate_flooring_calculator, title = {Flooring Calculator — Area, Boxes & Cost}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/flooring-calculator}}, year = {2026}, note = {TG we-Calculate} }
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