How to calculate how many tiles you need
Divide the area you're covering by the area of one tile, then add waste: Tiles = (Floor area × (1 + waste%)) ÷ tile area. Keep units consistent — a 60 × 60 cm tile covers 0.36 m², so a 12 m² floor needs 12 ÷ 0.36 ≈ 34 tiles before waste, ~37 with 10%.
Why you need a waste allowance
You can't lay whole tiles everywhere — edges and corners need cuts, some tiles break, and layouts like diagonal or herringbone waste more. 10% is standard for a simple straight layout; use 12–15% for diagonal, patterned, or small rooms with lots of cuts. Keeping a few spares also means a perfect match if one cracks years later.
Works for planks and flooring too
Enter your plank or laminate dimensions in place of the tile size and it works the same way. Since flooring is sold by the box, the calculator rounds up to whole boxes and shows the cost.
Should I buy by tile or box?
Tiles are usually sold by the box. The calculator rounds up to whole boxes so you buy enough — and it's worth having a spare box for repairs.
How much waste for a diagonal pattern?
Bump the waste slider to about 15%. Diagonal and herringbone layouts create far more cut pieces than a straight grid.
Do I subtract for cabinets or fixtures?
For a rough estimate, no — the waste allowance usually covers it. For large built-ins, reduce your area by their footprint first.