Flooring Calculator
Add every room, pick your material, and get boxes, tiles, or square yards needed, with a waste factor built in. Results update as you type. Need paint or floor area instead? Try the paint calculator or the square footage calculator.
| Room name | Length | Width | L-shape | Area | Remove |
|---|
- Total floor area
- 0 ft²
- With waste factor
- 0 ft²
- Boxes to buy
- 0
- Exact coverage needed
- 0 ft²
How to measure a room for flooring
Measure the length and width of each room at floor level with a tape measure, in the same units you plan to use throughout, and multiply them to get that room's square footage. If a room is not a simple rectangle, split it into two rectangles at the corner where it bends, the same way you would for a square footage calculation, and use the "Add L-shape" option on that row to add or subtract the second section.
Include closets, alcoves, and any other floor space the flooring will actually cover; do not subtract them out. Add multiple rooms using the "Add room" button if you are flooring a whole level or several connected spaces, since this calculator totals every row together before applying your waste factor and material math.
Pick your material type above. Plank flooring (laminate, vinyl plank, or engineered hardwood) is sold by the box with a coverage rating printed on the box, typically 18 to 24 square feet; enter that number to get exact boxes needed. Tile is sold by the piece or by the box, sized by width and height in inches or centimeters; enter the tile dimensions to get a tile count, and optionally a tiles-per-box number to get boxes too. Carpet is typically quoted by the square yard and installed from 12 foot wide rolls, so this calculator reports both square feet and square yards for carpet.
Always add a waste factor on top of the raw area. A straight-line install typically needs about 10 percent extra to cover cuts, trimming at walls, and the occasional damaged piece. A diagonal or herringbone layout wastes more material at every angled cut along the room's perimeter, so check the diagonal layout box above to add another 5 percent. Rooms with many corners, doorways, or built-in features often need even more, so round up rather than down when in doubt.
Worked example
A room measures 12 ft by 14 ft, installed with plank flooring at 10% waste, 20 sq ft per box.
Area = 12 × 14 = 168 sq ft.
With 10% waste: 168 × 1.10 = 184.8 sq ft of material to order.
Boxes needed = 184.8 ÷ 20 = 9.24 exact, rounded up to 10 boxes to buy.
Frequently asked questions
How much extra flooring should I buy?
Buy 10 percent more than your measured area for a straightforward rectangular room, which covers cuts, offcuts, and the occasional mistake. Add 5 percent more (15 percent total) for a diagonal or herringbone layout, since angled cuts waste more material. Complex room shapes with lots of corners or a large repeating pattern can need 15 to 20 percent even in a straight layout.
How many boxes of laminate do I need for a 12x12 room?
A 12 by 12 foot room is 144 square feet. With a 10 percent waste factor that is 158.4 square feet of material to order. At a common coverage of 20 square feet per box, that is 158.4 divided by 20, which rounds up to 8 boxes since you cannot buy a partial box. Always check the actual coverage printed on your chosen product's box, since it varies by brand and plank size.
How much extra tile do I need for a diagonal layout?
Add an extra 5 percent on top of your normal waste factor for a diagonal or herringbone tile layout, since every edge tile along the room's perimeter needs an angled cut and the offcuts are usually too small to reuse. Checking the "diagonal / herringbone layout" box in the calculator above adds that 5 percent automatically.
How do I convert square feet to square yards for carpet?
Divide square feet by 9 to get square yards, since one square yard equals 9 square feet (3 feet by 3 feet). For example, 168 square feet is 168 divided by 9, or about 18.67 square yards. Carpet is typically quoted and sold by the square yard, and most residential carpet comes on 12 foot wide rolls, so odd room widths can create extra seam waste.
Do I subtract closets when measuring for flooring?
No, include closets and any other enclosed floor space you plan to cover with the same flooring, since you still need material for that area. Add each closet as its own room row above, or fold it into an L-shaped extension of the main room if it shares a doorway with no threshold transition.
Can I return unopened boxes of flooring?
Most home improvement retailers accept unopened, undamaged boxes of flooring for return or store credit within a set window, often 90 days, but policies vary by store and by whether the product was a special order. Keep your receipt and buy an extra box or two using the waste factor above rather than cutting it close, since running short mid-install often means a delay waiting on a matching dye lot.