Tile Calculator
Find how many tiles you need for a floor or wall, including waste.
Results update as you type.
About this calculator
A tile calculator finds how many tiles you need for a floor or wall by dividing the area you are covering by the area of a single tile, then adding a waste allowance for cuts and breakages. Enter the room dimensions and the tile size and it handles the unit conversion — in metric it reads the room in metres and tiles in centimetres, in imperial the room in feet and tiles in inches.
Worked example: a 4 × 3 m floor is 12 m². With 30 × 30 cm tiles each covering 0.3 × 0.3 = 0.09 m², that is 12 ÷ 0.09 ≈ 134 tiles before waste, or about 147 once a 10% allowance is added. Enter the tiles per box (say 12) and it rounds up to 13 boxes; enter a price per tile and it multiplies through for a cost estimate.
Add a second surface under advanced options to tile a floor and a wall together, with a per-surface breakdown. Tilers and DIYers use it to order the right quantity — and to keep a few spare tiles from the same batch for future repairs.
Frequently asked questions
How many tiles do I need?
Divide the total area by the area of one tile, then add a waste margin. A 4×3 m floor is 12 m²; with 30×30 cm tiles (0.09 m² each) that is about 134 tiles, or 147 once a 10% waste allowance is added.
How do I work out boxes and cost?
Enter the tiles per box and the calculator rounds up to whole boxes; enter a price per tile and it multiplies by the tiles needed (including waste) for a total cost estimate.
How much waste should I allow for tiles?
A 10% allowance is normal for straight layouts, rising to 15–20% for diagonal patterns or rooms with many cuts. The extra covers breakages and off-cuts, and leaves spares for future repairs.
Can the tile calculator do a floor and a wall at the same time?
Yes — enter the second surface under advanced options and it adds both areas before working out the tiles, with a per-surface breakdown. Use the same tile size for both; run it twice if the two areas use different tiles.
Does it work for rectangular or large-format tiles?
Yes — enter the tile’s width and height separately, so a 60 × 30 cm plank or a 20 × 10 cm subway tile is handled correctly. The tool multiplies the two sides to get each tile’s area.
Why does the cost use tiles including waste?
Because you buy the spare tiles too — the cost multiplies the price by the total tiles needed after the waste allowance, matching what you will actually pay at the till rather than the bare coverage figure.
API — use this calculator from code
Call this calculator as a free JSON endpoint — no key required. Send the field values below as query parameters or JSON. Read the full API docs →
Endpoint
GET https://calculator.free/api/v1/tile/curl
curl "https://calculator.free/api/v1/tile/?units=metric&length=4&width=3&tile_w=30&tile_h=30"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/tile/?" + new URLSearchParams({
"units": "metric",
"length": "4",
"width": "3",
"tile_w": "30",
"tile_h": "30"
}));
const data = await r.json();
console.log(data.results);Results are estimates for general guidance only, not financial, medical or tax advice.