How to Calculate Floor Area and How Many Tiles You Need
Work out the floor area of a room and the number of tiles to buy, with extra for cutting and breakage. A simple method with examples.
Buying tiles is a small calculation with expensive consequences. Too few and you wait for a second delivery that may not match the shade; too many and you pay for tiles you cannot return. The Area and Tile Calculator gives a safe number in seconds.
Quick answer
Multiply room length by width to get the floor area. Divide by the area of one tile. Add 5 to 10 percent for cuts and breakage, then round up to whole tiles or whole boxes.
The method by hand
- Measure the room in metres, for example 4.2 m by 3.5 m.
- Floor area = 4.2 × 3.5 = 14.7 m².
- Tile size 60 cm × 60 cm = 0.6 × 0.6 = 0.36 m² per tile.
- Tiles needed = 14.7 ÷ 0.36 = 40.8, so 41 tiles.
- Add 10 percent for waste: 41 × 1.10 = 45 tiles.
If a box holds 4 tiles, buy 12 boxes (48 tiles) so you have a few spare for future repairs.
Using the calculator
Enter the room length and width in metres and the tile size in centimetres. The tool shows the floor area and the number of tiles with an allowance for cutting and breakage. Add tiles per box to see the boxes to buy.
Tips that save money
- Diagonal layouts and patterns waste more; allow 10 to 15 percent.
- Large tiles in small rooms create more offcuts than you expect.
- Subtract only big gaps. Do not subtract a small cupboard; fitted units often hide tile-free areas, but cutting around them costs tiles.
- Buy from one batch. Shades vary between production runs. Keep one spare box for repairs.
- Check grout lines. For large tiles with 3 mm joints the effect is small, but for mosaics include the joint in the tile size.
Privacy
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