Running out of tile mid-project is a nightmare — especially if the tile is discontinued or you can't match the batch. Getting your tile quantity right from the start saves time, money, and frustration.
The Basic Tile Calculation
- Measure the area to be tiled in square feet (length × width)
- Divide by the square footage of one tile to get the base quantity
- Add a waste factor based on the layout and tile size
Recommended Waste Factor
| Installation Type | Waste Factor to Add |
|---|---|
| Simple straight layout, square room | 10% |
| Diagonal (45°) layout | 15–20% |
| Herringbone or complex pattern | 15–25% |
| Room with lots of obstacles/cuts | 15–20% |
| Large format tiles (24×24 and up) | 15% |
Example Calculation
You're tiling a 10×12 ft bathroom floor with 12×12 inch tiles in a straight layout:
- Room area: 10 × 12 = 120 sq ft
- Each tile: 1 sq ft
- Base quantity: 120 tiles
- With 10% waste: 132 tiles → buy 135 (round up to a full box)
Pro Tip: Always buy from the same dye lot. Tile color can vary slightly between production batches. Order 10–15% extra from the start rather than going back to the store for more from a different batch.
Grout and Thin-set Estimates
| Material | Coverage |
|---|---|
| Thin-set mortar (50 lb bag) | 40–50 sq ft |
| Unsanded grout (10 lb bag) | 50–100 sq ft (1/8 inch joints) |
| Sanded grout (25 lb bag) | 50–75 sq ft (1/4 inch joints) |
Calculate Your Tile Needs
Enter your room dimensions and tile size to get exact tile quantities and material costs.
Use Tile Calculator →Choosing Tile Size for Your Space
- Small tiles (mosaic, 4×4) — Great for showers and backsplashes. More grout lines = more texture.
- Medium tiles (12×12, 6×6) — Versatile. Good for floors and walls in most rooms.
- Large format (18×18, 24×24) — Modern look. Makes small rooms appear larger. Requires very flat subfloor.