ToolsChoose a tool
How many tiles for 20 m² using 400×400 mm tiles?
You'll need 138 tiles to cover 20 m² with 400×400 mm tiles, including a 10% cutting waste allowance.
This is a mid-size tile, a reasonable balance between cutting waste and ease of handling.
| Area to tile | 20 m² |
|---|---|
| Tile size | 400 mm × 400 mm |
| Area per tile | 0.16 m² |
| Tiles per m² | 6.25 |
| Waste allowance | 10% |
| Area incl. waste | 22 m² |
| Tiles needed | 138 |
Assumptions
- 10% cutting/wastage allowance, the /site/materials calculator default.
- Straight (grid) lay. Diagonal, herringbone or feature layouts typically need more waste.
Check before you order: Confirm the exact tile size and lay pattern with your tiler — offset, diagonal and herringbone layouts all waste more than a straight lay — and buy a few extra of the same batch for future repairs.
How this is worked out & FAQ
How this is worked out
- Work out the area per tile from its width and length in mm.
- Add the waste allowance to the area you're tiling.
- Divide by the area per tile and round up.
FAQ
Does this allow for a pattern lay?
No — this is a straight lay allowance. Diagonal, herringbone or feature layouts need a higher waste percentage; use the calculator directly to raise it.
Should I buy extra for future repairs?
Yes — tile batches (and even the same range) can vary in shade between production runs, so keep spare tiles from the same batch rather than trying to match one later.
What if my area or tile size isn't listed?
Use the calculator directly at /site/materials — enter your own area and tile dimensions and it updates instantly.
Estimates only — allow for laps, cuts and site conditions. ← more tile count · All material calculators