Tile calculator: tiles and boxes for any room
The calculator needs JavaScript. The worked example, formula and figures below show exactly how it works, so you can do the sum yourself. A guide, not advice. Check your supplier's or maker's figures before ordering.
Short answer
Work out how many tiles and boxes to buy for a floor or wall, less doors and windows. Adhesive and grout have their own calculators. Enter your measurements below; every figure we start from is shown and you can change it.
Worked example
| You enter | Value |
|---|---|
| Area to tile | rectangle 4 m × 2.5 m |
| Tile length | 300 mm |
| Tile width | 300 mm |
| Joint width | 3 mm |
| Layout | Straight |
| Waste allowance | 10% |
You need 120 tiles
| Result | Value |
|---|---|
| Tiles | 120 |
| Area (after openings) | 10 m² |
Show the working
- Area: Area 1 10 m² = 10 m²
- Tiles: 10 m² × 1.1 (10% waste) ÷ (303 × 303 mm) = 119.81, rounded up to 120
How it works
- Tiles = area × (1 + waste) ÷ ((tile length + joint) × (tile width + joint)), rounded up
- Boxes = tiles ÷ tiles per box, rounded up
Tile adhesive and grout have their own calculators: the right amount depends on the product, the trowel notch and the joint, so they need their own inputs.
Our default (adjustable)
These are typical planning figures and our own allowances, not facts about your product. Change any of them in the calculator to match your bag, pack or tin.
| Figure | Our default (adjustable) | Kind | Source |
|---|---|---|---|
| Waste allowance: Straight | 10 % | Our assumption Not yet checked against the source | Our choice: change it to suit your job Cuts and breakages, straight lay. |
| Waste allowance: Diagonal or herringbone | 15 % | Our assumption Not yet checked against the source | Our choice: change it to suit your job More cuts on diagonal and herringbone. |
| Tiles per box | Enter from the bag, pack or tin | Common UK size Not yet checked against the source | From your product Enter from the box. |
FAQs
Guides
How many tiles do I need?
Work out tiles and boxes from your area and tile size, allow for joints and layout waste, and keep spares from the same batch.
Tile adhesive and grout quantities
How trowel notch changes adhesive coverage, how to read the bag, the grout formula and why to buy from one batch.