Tile Calculator
Calculate the number of tiles your floor needs, including a waste allowance.
m²
cm
cm
%
- 1
Tile area
(30 ÷ 100) × (30 ÷ 100) = 0.09One tile covers this many square metres. - 2
Base count
20 ÷ 0.09 = 222.22 - 3
With waste
222.22 × (1 + 10 ÷ 100) = 244.44 - 4
Tiles needed
⌈244.44⌉ = 245
Formula
How this is calculated
The calculator first works out how much floor one tile covers. Tile width and height are entered in centimetres, so each is divided by 100 to convert to metres, then multiplied together to give the area of a single tile in square metres. A 30 × 30 cm tile, for example, covers 0.30 × 0.30 = 0.09 m².
Next it divides the floor area (in m²) by that per-tile area to get the base count — the number of tiles needed if every one could be laid whole with no offcuts. To allow for cuts at edges, breakages and pattern matching, this count is multiplied by (1 + waste ÷ 100); a 10% allowance multiplies by 1.10. The final figure is rounded up with the ceiling function, because you can only buy whole tiles.
The model assumes a flat rectangular floor with no deductions for fixtures, ignores grout-joint width (which slightly reduces the tiles needed), and treats the waste percentage as a flat uplift. For diagonal layouts, large-format tiles or awkward room shapes, increase the waste allowance to 15% or more.
About this calculator
To tile a floor, divide the room area by the area of a single tile to get the base count, then add a waste allowance for cuts, off-cuts and breakages. Tile dimensions are entered in centimetres and converted to square metres, so a 30 × 30 cm tile covers 0.09 m². The result is rounded up because you cannot buy a fraction of a tile.
Frequently asked questions
Around 10% for a simple straight layout. Allow 15% or more for diagonal patterns, busy room shapes or large-format tiles.
You can only buy whole tiles, so any fractional requirement is rounded up to ensure you have enough to finish.
Enter tile width and height in centimetres; the calculator converts them to square metres to match the floor area.
Also known as
TG we-Calculate Editorial Team. (2026). Tile Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/tile-calculator
TG we-Calculate Editorial Team. "Tile Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/tile-calculator.
TG we-Calculate Editorial Team, "Tile Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/tile-calculator
@misc{wecalculate_tile_calculator, title = {Tile Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/tile-calculator}}, year = {2026}, note = {TG we-Calculate} }
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