Tile Calculator
Work out how many tiles to buy for any floor or wall — with the right waste allowance built in.
Last reviewed 2026-06-06
Tiling looks simple until you are standing in the store wondering whether 8 boxes is enough. Order too few and you risk a colour mismatch when you go back; order too many and you have wasted money on full boxes.
Enter the area you are tiling and the size of a single tile, then pick a waste allowance. We convert everything to a like-for-like area, add the waste for cuts and breakage, and tell you exactly how many tiles to buy.
How to use the Tile Calculator
- Measure the length and width of the floor or wall you are tiling.
- Enter the size of one tile (most boxes print this on the label).
- Pick a waste allowance: 10% for a straight layout, more for diagonal patterns or rooms with lots of cuts.
- Read off the total number of tiles and buy them all in one batch.
Frequently asked questions
How much extra tile should I buy for waste?
Add about 10% for a simple, straight layout. Increase to 15% for diagonal or herringbone patterns, and up to 20% for small or awkward rooms with many cuts. The extra also covers the occasional cracked tile.
Should I calculate by tile or by the box?
Calculate the number of tiles first, then divide by the tiles-per-box printed on the packaging and round up. This calculator gives you the tile count including waste so you can convert to whole boxes confidently.
Why buy all the tiles at once?
Tiles are made in batches called dye lots, and colour can vary slightly between lots. Buying everything together — plus a spare box — guarantees a consistent finish and a match for future repairs.
Does this work for wall tiles too?
Yes. Measure the wall area exactly as you would a floor and enter the tile size. For walls with windows or fixtures, you can subtract those areas from the length × width before entering, or simply rely on the waste allowance.