How do you calculate how many tiles you need?
Tiles per m² come from the tile size plus the joint width: tiles/m² = 1 / ((width + joint) × (length + joint)). Multiply by the area and add cutting waste. Allow at least 5–10%, and more for diagonal layouts, many corners or large formats. Buy tiles from the same production batch (same shade).
Frequently asked questions
How much waste should I allow?
Straight layout: 5–10%. Diagonal or herringbone: 10–15%. Awkward rooms with many corners can be higher.
Does the joint width really matter?
Yes. For large tiles and narrow joints the effect is small, but for small tiles or wide joints it noticeably changes the count per m².
Do I count per box or per tile?
This tool gives pieces. Divide by the tiles per box (on the packaging) and round up.
Does this work for wall tiles?
Yes, the calculation is the same — just enter the wall dimensions instead of the floor.