Flooring Calculator — Quick Estimate
Work out how many boxes of flooring a room needs, with a waste allowance for cuts.
Need exact piece counts, offcut reuse, or an L/T-shaped room? Try the advanced calculator →
Room dimensions
Waste & packaging
How this is calculated
Room area is length × width. A waste allowance is added on top to cover offcuts from trimming around the edges and diagonal cuts — 10% is a reasonable default for a simple rectangular room, more for irregular layouts or diagonal installs. That total is divided by how much area one box covers (check the box label — coverage varies by product) to get the number of boxes, rounded up. Underlayment is quoted at the raw room area, without the waste allowance, since underlayment offcuts are rarely usable elsewhere.
Common questions
Do I need underlayment separately from the flooring itself?
Usually yes — most floating floors (laminate, engineered wood, vinyl click) need a separate underlayment layer for cushioning, sound dampening, or moisture protection. Check your flooring's installation instructions.
How much waste should I allow for a diagonal or herringbone install?
More than a simple straight layout — 15-20% is a common starting point for diagonal installs, versus 5-10% for a straightforward rectangular room, because more boards get cut at an angle and the offcuts are less likely to be reusable.
My room isn't a plain rectangle, or I know my plank size — is there a more precise option?
Yes — the advanced calculator simulates the actual row-by-row plank layout (exact piece count and offcuts, not just an area estimate) and supports L- and T-shaped rooms.
Part of Home Improvement Calculators