BuildEstimate

Free calculator

Tile calculator

Enter the area, the tile size and the grout gap, and get the number of tiles to buy with waste, and how many boxes.

Result

Area to tile
12 m²
Tiles (exact)
131
To buy with 10% waste
144
Boxes
enter tiles per box

Keep a few spare tiles from the same batch for future repairs; colours vary between batches.

How it works

Each tile takes up its own size plus one grout joint along each side. Tiles = area ÷ ((tile length + grout) × (tile width + grout)). The result is rounded up, then the waste allowance is added and rounded up again.

Ten percent waste is usual for a straight layout in a rectangular room. Use 15% for a diagonal or herringbone pattern, or for rooms with many corners and pipes. Large-format tiles waste more per cut, so keep the allowance even if the tile count is small.

Buy all boxes from the same batch number; shade and size can differ between batches. Keep a few spare tiles for future repairs.

Frequently asked questions

How many 30 x 30 cm tiles do I need for 10 m²?
With a 3 mm grout gap, about 109 tiles. With 10% waste, buy 120, which is 12 boxes of 10.
How many 12 x 12 inch tiles per square foot?
One, before waste, if you ignore the grout gap; slightly less than one with a normal gap. For 100 sq ft with 10% waste, buy 110.
What waste percentage should I use for tiles?
10% for straight layouts, 15% for diagonal or patterned layouts, and more for small or awkward rooms.

Guides