Ordering tiles is a balance: too few and you risk a mismatched top-up batch, too many and you've wasted money. This calculator gives you a solid number, including the all-important waste allowance.
The core calculation
It's simple in principle — total area divided by the area of one tile. The nuance is waste: every real job needs tiles cut to fit edges, corners and around pipes or sockets, and a few will crack. That's why a raw count is never enough.
Choosing a waste percentage
A straightforward grid on a rectangular floor wastes little, so 10% is plenty. Diagonal and herringbone layouts produce far more offcuts, and busy rooms with many obstacles need more cuts — bump the allowance to 15–20% for those.
Frequently asked questions
Divide the total area you're tiling by the area of a single tile, then add 10–20% for waste. For example, a 12 m² floor with 30×30 cm tiles (0.09 m² each) needs about 133 tiles plus waste.
Around 10% for a simple straight layout, and 15–20% for diagonal patterns, herringbone, or rooms with many corners and fixtures that require cuts.
Yes — always buy a little more than the calculation and keep spares. Future production batches can differ slightly in shade, making an exact match hard later.