Flooring Calculator
Turn room dimensions into total square feet and the number of boxes to buy.
Room area
120 sq ft
Total with waste
132 sq ft
Boxes needed
7 boxes
An estimate for planning only. Runs entirely in your browser and nothing is uploaded.
How to use this tool
- Measure the room length and width in feet and type them in.
- Set a waste allowance percent for cuts, mistakes, and pattern matching. Ten percent is a common starting point.
- Enter the coverage per box printed on your tile, laminate, or hardwood packaging.
- Click Calculate to see the room area, the total square feet with waste added, and how many full boxes to buy.
How it works
The flooring calculator finds the room area in square feet, adds your waste allowance, then divides by the coverage one box holds. Because you cannot buy part of a box, the box count is always rounded up.
For an oddly shaped room, split it into rectangles, run each piece through the tool, and add the results together. The waste percent covers diagonal layouts, herringbone patterns, and the offcuts you cannot reuse.
A real example
Say a bedroom is 12 feet by 10 feet. The base area is 120 square feet. With a 10 percent waste allowance the total becomes 132 square feet. If each box of laminate covers 20 square feet, that is 132 divided by 20, which is 6.6 boxes, rounded up to 7 boxes. The extra also leaves you a few planks for future repairs.
Common questions
How much waste should I add for tile?
For a straight layout, 10 percent is typical. For diagonal or patterned tile coverage, many installers use 15 percent because more pieces get cut. Add more for rooms with lots of corners and angles.
Does this work for carpet, laminate, and hardwood?
Yes. The math is the same for any flooring sold by square feet per box or roll. Enter the coverage per box from the product label and you get a carpet, laminate, or hardwood estimate the same way.
Why does it always round up the boxes?
Stores sell full boxes, not partial ones. Rounding up guarantees you have enough material to finish the room without a second trip mid project.
My room is not a perfect rectangle. What do I do?
Break the floor into rectangles, calculate each one, then add the totals. For closets or alcoves, measure them as separate pieces and include them in the sum.
Should I buy exactly the number shown?
The result is a planning estimate, not professional advice. Confirm measurements on site, keep a spare box for repairs, and check the supplier return policy before ordering.