CalculatorEnter your measurements below and it works the answer out.
Area divided by the tile, plus 10% waste, rounded up — then into whole boxes. Add your box coverage for the number you actually buy.
The arithmetic. Work out the area, divide by what one tile covers, add 10% waste, round up. Nothing more than that — the value of the page is the coverage figures and the waste allowance, both of which are stated here rather than hidden inside the tool.
Why the waste allowance is 10%. Ten per cent extra is the allowance for a floor laid square to the walls. Go to fifteen for a diagonal or herringbone layout, and keep a full box back — tile is made in batches and a replacement in two years will not match.
How it is sold. Tile is sold by the box and priced by the square foot. Box coverage differs by product, so this gives you tiles and square feet and leaves the box count to the label in front of you.
Layout decides the waste, not the room. A floor laid square to the walls loses least; a diagonal or herringbone layout loses more, because every edge tile is cut twice. Set out from the center so the cuts land evenly on both sides, and keep a full box back — dye lots change between production runs.
Round up to how it is sold. The result below shows three numbers: the raw quantity, the quantity after the 10% allowance, and the whole tiles to buy. You can see exactly where the rounding happened rather than being handed one figure.
Divide your area in square feet by the coverage of one tile, then add 10% and round up. At 1 sq ft each, a 200 sq ft job needs 220.
10% is what this calculator adds. Ten per cent extra is the allowance for a floor laid square to the walls. Go to fifteen for a diagonal or herringbone layout, and keep a full box back — tile is made in batches and a replacement in two years will not match.
Ten per cent for a straight layout, fifteen for diagonal or herringbone, and a spare box on top for future repairs. Dye lots change between production runs, so a box bought later rarely matches.
Free to use on any site, including commercial ones. Paste this where you want it to appear — it keeps working when we update the figures.