Free tool
Flooring Calculator: How Much Flooring Do I Need?
Work out how much flooring to buy for one or more rooms. Add waste for your layout, round up to full boxes, or switch to carpet square yards. Free and instant.
How to use the Flooring Calculator
- Choose boxes (planks, laminate, vinyl or tile) or carpet.
- Enter the length and width of each room. Add a row for every room.
- Set the waste percent for your layout and the square feet per box from the package.
- Read the boxes to buy, the area you will have left over and, with a price, the cost.
How the flooring calculator works
For each room the calculator multiplies length by width, adds the rooms together, and then adds your waste allowance. It divides by the square feet in one box and rounds up to whole boxes.
Boxes needed = (floor area x (1 + waste percent)) / square feet per box, rounded up
Worked example
A 12 by 15 foot living room and a 10 by 10 foot den:
- Floor area: 180 + 100 = 280 sq ft
- With 10 percent waste: 308 sq ft
- At 20 sq ft per box: 15.4, rounded up to 16 boxes (17 with a spare box)
- You buy 340 sq ft, so about 60 sq ft is left over
How much waste to add
| Situation | Common waste allowance |
|---|---|
| Straight layout, simple rectangular room | About 10% |
| Diagonal layout, herringbone or a busy pattern | 15% to 20% |
| Many corners, closets or built-ins | Toward the higher end |
| Large-format tile or a complex pattern | 15% to 20% |
These are common guidelines from flooring and tile guides, and they vary by source. Your installer or the manufacturer's installation guide is the best source for your product.
Carpet
Carpet is sold by the square yard, which is 9 square feet. It also comes on a roll of fixed width, so the length you must buy can be more than the room area suggests, and stairs, hallways and seams need extra. Switch to carpet to see the square yards, then ask the store to lay the rooms out on a roll.
Tile and planks
The calculator covers tile, laminate, vinyl plank and hardwood as boxes, because they are all sold by coverage per box. Enter the square feet per box from the package. For tile, also check the tile and grout joint size with your installer.
Before you order
Measure each room separately, include closets and alcoves, and round measurements up. Keep the manufacturer's installation requirements, such as acclimation time for wood, with your plan. For very large areas, our lot size and square feet to acres calculator converts the units.
More home project calculators
Replacing the roof too? Try the roofing calculator. Covering walls instead? See the wallpaper calculator. For a wood fence, use the fence cost calculator.
Frequently asked questions
How much flooring do I need for a 12 by 12 foot room?
The room is 144 square feet. With 10 percent waste you need 158.4 square feet, which is 8 boxes if each box covers 20 square feet (7.92 rounded up).
How much waste should I add for flooring?
Many guides use about 10 percent for a straight layout in a simple room, and 15 to 20 percent for diagonal layouts, patterns, many corners or large tiles. Some sources use lower figures for simple vinyl plank installs, so check your product's installation guide.
Why round up to full boxes?
Flooring is sold by the unopened box, so you cannot buy a part of one. The calculator rounds up so you do not come up short.
Should I buy an extra box for repairs?
Several sources suggest one spare box, because the color or dye lot of a later order may not match. Tick the spare box option to add one.
How many square feet are in a square yard of carpet?
Nine. A 12 by 15 foot room is 180 square feet, and with 10 percent waste (198 square feet) it needs 22 square yards.