Explanation
Tile count by dimensions
Tile dimensions in centimetres give an area in square centimetres. Converting the surface area consistently and rounding up gives a first estimate of the number of tiles to buy.
Measure the surface and one tile
Enter the net area in square metres and the face dimensions of one tile in centimetres. Set the allowance explicitly for cutting, breakage and spare tiles; 10% is a common starting point.
N = ⌈A × 10000 × (1 + a/100) ÷ (w × h)⌉
| N | Whole tiles to buy |
|---|---|
| A | Area to tile |
| w | Tile width |
| h | Tile height |
| a | Cutting allowance |
50 cm square tiles on 10 m²
| Area to tile | 10 |
|---|---|
| Tile width | 50 |
| Tile height | 50 |
| Cutting allowance | 10 |
| Result | 44 tiles |
One tile is 50 cm × 50 cm. 10 m² × 10,000 cm²/m² × (1 + 10/100) ÷ tile face, rounded up = 44 tiles.
25 cm square tiles on 1 m²
| Area to tile | 1 |
|---|---|
| Tile width | 25 |
| Tile height | 25 |
| Cutting allowance | 0 |
| Result | 16 tiles |
One tile is 25 cm × 25 cm. 1 m² × 10,000 cm²/m² × (1 + 0/100) ÷ tile face, rounded up = 16 tiles.
A count requiring rounding
| Area to tile | 1 |
|---|---|
| Tile width | 30 |
| Tile height | 30 |
| Cutting allowance | 0 |
| Result | 12 tiles |
One tile is 30 cm × 30 cm. 1 m² × 10,000 cm²/m² × (1 + 0/100) ÷ tile face, rounded up = 12 tiles.
Diagram of this result
Filled squares are whole tiles; the part-filled square is the share of the last tile you need. Grout joints and layout cuts are not modelled.
The exact tile count before rounding and the whole tiles to buy are stated as numbers under the grid.
Common mistakes
Do not mix millimetres with centimetres. The count treats tiles as continuous coverage; grout spacing and layout can change the actual count.
Assumptions and limits
Uniform rectangular tiles, positive dimensions and area up to one million; allowance 0–100%. Counts round up after applying allowance. Layout, joint width, edge cuts and tiles per box are not inferred. Material estimates only; verify measurements, product guidance and site requirements before ordering.
Does this include grout joints?
No. It divides the surface by the tile face area. A detailed layout with the selected joint width is needed for a more exact count.
Method and references
Square metres converted to square centimetres (× 10,000), scaled by an explicit percentage allowance, divided by one tile’s face area and rounded up once at the end. Box quantities and allowances must come from the chosen product.