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How many tiles do I need?

Get a tile count and box total from your room and tile size, with wastage built in.

Tile layout for the floor of a 4.2 m by 3.1 m room, using 300 by 600 mm tiles, with cut tiles shown at the edgesTile layout, laid flat (77 to cover, 7 cut - before wastage)3.1 m wide · 4.2 m deep

Your room

m
m
m
Doors
1
Windows
1
Surface
Your product300×600mm tiles · 6/box (from tile size) · 10% wastageChange
Tile size

From your tile size — tiles are sold by the m², about 1.1 m² a box. Check yours.

Wastage

14 boxes (80 tiles)

Floor area
13 m²
× 10% wastage
14.3 m²
÷ 300×600 mm tile (0.18 m² each)
80 tiles
÷ 6 per box (~1.1 m² boxes)
14 boxes

about 4 tiles spare

How we work it out

  • We calculate the area to be tiled - floor or walls - the same way as our other calculators, with doors and windows taken off wall areas.
  • A wastage allowance is added on top for cuts, breakages and awkward corners before we work out the tile count.
  • Tile count is based on your tile's exact size in millimetres, converted to square metres per tile.
  • The final count is rounded up to whole boxes as sold, since most suppliers only sell tiles by the box.

Frequently asked questions

How many tiles do I need per m²?

It depends entirely on tile size. A 300x300mm tile covers 0.09 m², so you'd need about 11 tiles per m² before wastage. A larger 600x600mm tile covers 0.36 m², so just under 3 per m². Enter your tile size above for an exact figure.

Do I need to add wastage for tiling?

Yes - 10% is a sensible default for a straightforward rectangular room. Complex layouts, diagonal patterns, small bathrooms with lots of cuts around fittings, or a first-time tiler should budget 15-20% to be safe.

How many tile boxes should I buy?

Always round up to the next whole box, then check the batch number matches across boxes - tile colour can vary slightly between production runs, which is much more noticeable if you have to buy a top-up box later.

Should I measure floor or wall area for tiles?

Floor tiling uses the plain floor area (length x width). Wall tiling uses the same wall-area calculation as paint, with standard doors and windows subtracted - pick the right surface above.

Want to see this in your actual room? Try it with DreamDIY