Tile Calculator
Tiles = area ÷ tile area × (1 + waste) — enter the area in metres, the tile size in centimetres and a waste allowance for cuts.
Reviewed by the OmniCalc teamMethod verified 2026-07-01
Area
Tile size
147tiles
= 134 tiles without waste= 12 m²
Tiles needed 147, area 12 m²Covering 12 m² needs 147 tiles (134 + 13 for waste).
Show steps
- Area = length × width = 4 × 3 = 12 m².
- One tile area = (30 ÷ 100) × (30 ÷ 100) = 0.09 m².
- Tiles without waste = ceil(12 ÷ 0.09) = 134.
- Tiles needed = ceil(12 ÷ 0.09 × (1 + 10 ÷ 100)) = 147.
How to use the tile calculator
- 1Enter the area length and width you want to cover, in metres.
- 2Set the tile length and width in centimetres — as printed on the box.
- 3Choose a waste percentage for cuts and breakages (usually 10%) and read the tiles needed, with the working under Show steps.
Buy from a single batch
Tiles are made in batches, and the colour can shift slightly from one batch to the next. Counting the tiles that wasteallows for lets you buy everything in one order from the same batch — so you don’t end up with a visible colour mismatch from a separate top-up purchase later.
Frequently asked questions
How many tiles do I need?
Divide the area you want to cover by the area of a single tile, then multiply by a waste allowance and round up: tiles = ceil(area ÷ tile area × (1 + waste ÷ 100)). A 4 m × 3 m floor with 30 × 30 cm tiles and 10% waste needs 147 tiles.
Why convert the tile size to metres?
The area is in square metres, so the tile must be too. A tile measured in centimetres is converted by dividing each side by 100 — a 30 cm side is 0.30 m, so a 30 × 30 cm tile is 0.09 m². Dividing the floor area by that gives a like-for-like tile count.
How much waste should I add?
10% is the usual default for a straightforward straight-lay floor. Add more — 15% or higher — for diagonal patterns, lots of cuts around fixtures, or a small room where a single broken tile is a bigger share of the total. The extra also gives you spares for future repairs.