How Many Tiles Do You Need?
Tile is unforgiving to under-order: a matching dye lot may be gone by the time you're three rows short, and a visible color shift across one wall reads as a mistake forever. Over-ordering hurts less but wastes real money on premium tile. The fix is a proper count with an honest waste factor before you buy.
Enter the area's dimensions and your tile's size (any size — the common formats are just presets of the same math), pick straight or diagonal waste, and you get the exact count, the coverage area, and each tile's face area. For multiple rooms or walls, run each and sum — or add the areas first if the tile matches.
Need the area itself first? Measure it with the Square Footage Calculator.
How to Calculate Tiles for a Floor or Wall
Everything reduces to face areas in the same unit:
Tiles = (Area in in²) ÷ (tile width × tile length) Order = Tiles × (1 + waste%) → rounded up
Worked example: a 10 × 12 ft floor is 120 sq ft = 17,280 in². With 12″ × 12″ tiles (144 in² each) that's exactly 120 tiles; adding 10% cut waste makes the order 132 tiles. The same floor in 12″ × 24″ tile needs 66.
Tile Chart: Tiles per Square Foot by Size
The common formats, with a 100 sq ft example order at 10% waste (all computed by this calculator's formula):
| Tile size | Tiles per sq ft | 100 sq ft + 10% waste |
|---|---|---|
| 3″ × 6″ (subway) | 8.00 | 881 tiles |
| 12″ × 12″ | 1.00 | 111 tiles |
| 6″ × 24″ (plank) | 1.00 | 111 tiles |
| 12″ × 24″ | 0.50 | 56 tiles |
| 18″ × 18″ | 0.44 | 49 tiles |
| 24″ × 24″ | 0.25 | 28 tiles |
Boxes vary by brand — divide your tile count by the tiles-per-box printed on the carton, and round the boxes up too.
Ordering and Layout Tips That Prevent Short Orders
The habits that separate clean tile jobs from short orders:
- Buy everything in one order and check dye-lot numbers match across boxes — lots shift color slightly between production runs.
- Use 15% waste for diagonal, herringbone, or any layout with a pattern repeat; every border row gets cut and offcuts often can't be reused.
- Square your layout with the 3-4-5 rule: measure 3 ft along one wall and 4 ft along the other — the diagonal between marks reads exactly 5 ft when the angle is square.
- Dry-lay a row before setting: it exposes awkward slivers at walls, which you fix by shifting the starting line, not by cutting 1-inch strips.
- Keep a few spares after the job — a matching repair tile years later is worth far more than the shelf space.
If your room is far from rectangular, split it into rectangles, run each, and sum the tile counts before applying the box math.
What Tile Installation Costs
Installed tile cost has two parts: material (your tile count × price per tile, or area × price per square foot) and labor, which is quoted per square foot and usually exceeds the material for standard ceramic. Example math at illustrative prices: a 120 sq ft floor in mid-range tile at $4 per sq ft of material is $480, and labor at $8 per sq ft adds $960 — $1,440 installed, of which two-thirds is labor. Your local quotes replace those numbers; the structure of the math stays.
Beyond tile and labor, real quotes include setting materials (thinset, grout, spacers — commonly 10–15% on top of tile), substrate work if the floor needs leveling or backer board, and tear-out of old flooring. Complexity moves labor more than material: diagonal or herringbone layouts, small-format tile, and niche work all price higher per square foot. Get the tile count from this calculator, then price that count locally.