Tile is one of the easier materials to estimate — and one of the most annoying to come up short on, because a second order often arrives a shade off. Here's how to get the number right the first time.
Start with square footage
Measure the area in feet and multiply length × width. For an L-shaped room or a wall with a window, break it into rectangles, measure each, and add them up (subtract big openings like a doorway). Our tile calculator turns area + tile size straight into a tile count.
Divide by your tile's size
A 12×12-inch tile covers exactly 1 square foot, so the tile count equals the square footage. For other sizes, divide the area by the tile's coverage: tile length × width ÷ 144. A 6×24-inch plank tile also covers 1 sq ft (6 × 24 ÷ 144 = 1), while a 4×4 covers just 0.11 sq ft — about nine per square foot.
Add the right waste percentage
- 10% — a straight (grid) layout in a simple rectangular room.
- 15% — diagonal or herringbone layouts, which create more cut pieces.
- 20% — large-format tile, very small rooms, or lots of angles and niches.
Waste covers edge cuts, the occasional cracked tile, and keeping a few spares for repairs.
Don't forget the rest of the job
Tile count is only part of the list. You'll also need thinset mortar and grout (both depend on tile size and spacing), spacers, and possibly backer board or underlayment. For a floor build-up, the underlayment calculator helps.
Buy from one lot
Tile is produced in batches, and shade and size drift slightly between them. Buy all your tile — including the waste allowance — in one order from the same lot, and keep a spare box sealed. Match it once, and the floor matches forever.