Tile calculator

Formula

How it works

Divide the room area by the area of one tile and add an allowance for cuts and breakage (about 10% is typical for straight layouts).

Worked example

The same calculation with the default values:

• Room length 5 m
• Room width 3.5 m
• Tile length 60 cm
• Tile width 30 cm
• Waste allowance 10 %

1. room area = 5 × 3.5 = 17.5 m²
2. tile area = 0.6 m × 0.3 m = 0.18 m²
3. tiles = 17.5 ÷ 0.18 = 97.222222
4. tiles with waste = ⌈97.222222 × (1 + 10 ÷ 100)⌉ = 107

Result: Room area: 17.5 m² · Area of one tile: 0.18 m² · Tiles without waste: 98

Common mistakes

• Forgetting the waste allowance for cuts - tiles near edges, around fixtures, and diagonal layouts always produce offcuts, so ordering the exact mathematical minimum almost always leaves the job short.
• Mixing up the units of room area and tile area (e.g. room in square meters, tile size in centimeters) - both must be converted to the same unit before dividing.
• Ignoring that tiles are sold in whole boxes, not individual units - the real amount to purchase is rounded up to the nearest full box, which can be noticeably more than this calculator's raw tile count.