How it works
Tiles = total area × (1 + waste %) ÷ area of one tile plus its grout joint, rounded up. Enter each floor or wall as its own area, your tile size, and the joint width you’ll use.
| Tile | Tiles per sq ft (1/8" joint) | Tiles per m² (3 mm joint) |
|---|---|---|
| 4 × 4" (100 × 100 mm) | about 8.5 | about 94 |
| 12 × 12" (300 × 300 mm) | about 0.98 | about 10.9 |
| 12 × 24" (300 × 600 mm) | about 0.49 | about 5.5 |
| 24 × 24" (600 × 600 mm) | about 0.25 | about 2.8 |
Before waste. The calculator works these out for any size.
Tips
- Buy all tiles from the same batch (check the shade and lot code on the box).
- Keep a few spare tiles for future cracked-tile repairs.
- Large tiles need a very flat surface. Plan for levelling compound if the floor isn’t flat.
Full guide: how many tiles do I need?
FAQ
How much extra tile should I buy?
About 10% for a straight grid layout, 15% for diagonal and 15–20% for herringbone or small rooms with many cuts. For large-format tiles, add a little more, because each broken tile is a bigger loss.
Does grout spacing change how many tiles I need?
Slightly. Wider joints mean each tile covers a little more area, so you need a few fewer tiles. The calculator includes the joint.
How do I calculate tiles for a shower wall?
Measure each wall’s width × height as a separate area, plus the floor and any niche. Add them with the “add another area” button.
Should I subtract the door or window?
For small openings, no; the extra covers cuts and breakage. For a large window or a patio door, subtract it.