How much tile do I need? Layout, cuts and boxes
Measure each surface, add about 10% for cuts and breakage (15% for diagonal or herringbone) and round up to whole boxes. The tile calculator lays out every tile, so you see which ones are cut before you buy.
A 12 × 10 ft floor in 24 × 12 inch tile takes 60 tile positions, 15 of them cut. With 10% extra that is 66 tiles: 7 boxes of 10.
Worked example
Example: one 12 × 10 ft floor, 24 × 12 inch tile, a 1/8-inch joint, 10 tiles to a box and 10% extra.
This example gives 7 boxes of tile.
| Pieces | Along the length × along the width | Cut |
|---|---|---|
| 9 | 23.38 in × 12 in | straight |
| 5 | 24 in × 10.88 in | straight |
| 1 | 23.38 in × 10.88 in | straight |
- Surface 1: 45 full + 15 cut = 60 tile positions
- 60 × (1 + 10/100), rounded up = 66 tiles
- ceil(66 / 10) = 7 boxes
- Thinset: 120 sq ft ÷ 42 sq ft a 50 lb bag (CUSTOM VersaBond-LFT with a 3/4 × 9/16 in U-notch at 30° trowel; its chart gives 42 to 47) = 2.86 bags
- Grout: 24 in × 12 in tile, 3/8 in deep, 1/8 in joints: about 461 sq ft a 25 lb bag (CUSTOM’s Polyblend Plus chart, worked for this size); 120 ÷ 461 = 0.26 bags
Other calculators for this job
Every step of a flooring project: measure, the list, what it costs and the quotes.
Tile waste by layout
This guide’s 12 × 10 ft floor with 1/8 in joints, counted by the tile calculator: every cut position takes a whole tile, and no extra is added yet. The percentage is how many more tiles the layout takes than a straight lay of the same tile. Diagonal and herringbone layouts are cut at an angle along every wall, so they take the most, and more with longer tiles. Offset rows move half a tile, except tiles longer than 15 in: the U.S. tile installation standard, ANSI A108.02, offsets those by a third at most, unless their maker allows more. Add your extra for breakage on top, and try your own room and tile in the calculator: reusing offcuts can bring the count down.
| Layout | 12 × 12 in tile | 24 × 12 in tile | 24 × 6 in plank |
|---|---|---|---|
| Straight | 120 tiles | 60 tiles | 120 tiles |
| Offset | 125 tiles, 4% more, offset half | 66 tiles, 10% more, offset a third | 133 tiles, 11% more, offset a third |
| Diagonal | 135 tiles, 13% more | 79 tiles, 32% more | 152 tiles, 27% more |
| Herringbone | Needs a rectangular tile | 84 tiles, 40% more | 167 tiles, 39% more |
What changes the order?
The same floor and tile laid in a different pattern has different border cuts, so the box count changes. Each cut position takes a new tile here.
| Calculator input | Result from those inputs |
|---|---|
| Layout pattern: straight | 7 boxes of tile |
| Layout pattern: offset by a third of a tile | 8 boxes of tile |
| Layout pattern: diagonal | 9 boxes of tile |
| Layout pattern: herringbone | 10 boxes of tile |
Try your own measurements in the tile calculator.
Measure each surface on its own
Floors, walls and backsplashes are separate rectangles; an L-shaped room is one rectangle with a corner taken out. In a shower, measure each wall, the floor, the curb and the niche separately, because they often use different tile.
Try a starting point
Where the first full tile sits decides how big the border cuts are. Try a few starting points (the calculator can try them for you) and keep the one that leaves no thin slivers at the doorway or along the wall you see most.
Extra, then whole boxes
Add about 10% for a straight or offset layout and about 15% for diagonal or herringbone, then round up to whole boxes. Buy every box from one lot so the color matches, and keep a few spare tiles for repairs.
Grout, mortar and the rest
Thinset depends on the trowel and grout on the tile size and joint: the tile calculator counts both from CUSTOM’s charts, or from the coverage on your own bags. Waterproofing, backer board, trim pieces and movement joints are separate lines; ask the installer which ones the quote includes.