Work out how many tiles you need for a floor, wall or splashback from the area and the tile size. The result includes a waste allowance and an estimate of adhesive and grout bags.
Your shopping list
How to measure
- Measure the length and width of the floor or wall to be tiled.
- Subtract large areas you will not tile, such as a bath, shower tray or fitted cupboard.
- Use the actual tile size on the box, not including grout lines.
The formula
Area = length × width Tiles = (area × (1 + waste %)) ÷ area of one tile (round up)
Worked example
A 10 × 8 ft floor is 80 sq ft. A 12 × 12 in tile covers 1 sq ft. With 10% waste you need 88 tiles. In metric, a 3 × 2.4 m floor with 30 × 30 cm tiles needs 88 tiles.
Tips before you buy
- Buy all tiles from the same batch number so the shade matches.
- Large-format tiles break more easily when cut. Allow 15% waste.
- Dry-lay a row first to plan where the cut tiles will fall.
Frequently asked questions
How much waste for tiles?
10% for simple straight layouts, 15% for diagonal layouts or large-format tiles.
Should I buy all tiles at once?
Yes. Batches vary slightly in colour, so buy enough from one batch, plus a few spares for repairs.
How much tile adhesive do I need?
Roughly one 20 kg bag per 4–5 m² (one 50 lb bag per 80–100 sq ft) with a standard notched trowel. Larger tiles need a bigger notch and more adhesive.
Results are estimates for planning only. Always check quantities with your supplier before you buy.