How many tiles do I need?

Divide the area you are tiling by the area of one tile, then add a waste allowance for cuts and breakages. The calculator does this for you once you enter the area and the tile size, and a typical waste allowance is 10%.

How much waste should I allow?

Around 10% is normal for a simple layout. Allow more, up to 15% or 20%, for diagonal patterns, lots of cuts, or large format tiles, and keep a few spares for future repairs.

How do I work out the tile size in square metres?

Multiply the tile width by its height in metres. A 300 by 300 mm tile is 0.3 by 0.3, which is 0.09 square metres, so it takes about 11 tiles to cover a square metre. The calculator handles this from the millimetre sizes you enter.

Tile Calculator

Work out how many tiles to buy for a floor or wall. Enter the area to tile, the size of one tile, and a waste allowance for cuts and breakages. The calculator shows the number of tiles, including waste, so you order the right amount with a few spares left over.

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Area to tile (m²)

Tile width (mm)

Tile height (mm)

Waste

0 tiles

to buy, including waste

Tiles for the area0

Tiles per m²0

How it works

One tile covers its width times its height. Divide the area you are tiling by that to get the base number of tiles, then add the waste percentage for cuts and breakages. The calculator rounds up to whole tiles, since you cannot buy part of one.

Worked example

For 12 square metres with 300 by 300 mm tiles, each tile covers 0.09 square metres, so you need about 134 tiles for the area. Adding 10% waste takes it to around 147 tiles to buy.

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Square Metre Calculator: work out an area.
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Paint Calculator: paint for walls.
Area Conversion Calculator: convert area units.

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