Calculate how many tiles you need for a floor or wall from the area and tile size, including a waste allowance for cuts and breakages.
The waste allowance covers cut tiles at edges and the occasional breakage. Ten percent is typical for a simple layout; use 15 percent or more for diagonal patterns or rooms with many corners.
Divide the area you are covering by the area of one tile, then add a waste allowance. For example a 30 by 30 cm tile covers 0.09 m², so a 12 m² floor needs about 134 tiles before waste.
Around 10 percent is normal to cover edge cuts and breakages. Increase it to 15 percent or more for diagonal or herringbone layouts, small rooms with many cuts, or large-format tiles.
Yes. Tile colour can vary slightly between production batches, so buying all you need at once, including the waste, helps the finish stay consistent.