How many tiles do I need
Tiles required based on tile size and the area to cover.
Calculator inputs
Results
Enter your values and press “Calculate” to see the result.
In short
- What it calculates
- Tiles required based on tile size and the area to cover.
- Formula used
Tile area = width × height (in metres)- Example
- 20 m² with 30 × 60 cm tiles and 10% waste:
Tile calculator
Tiling always leaves offcuts, especially with large formats and rooms with many corners. That is why a waste allowance keeps you from running short.
How it works
The area of a single tile is derived from its dimensions and the total area is divided by it, increased by the waste allowance you set.
Formula
Tile area = width × height (in metres)
Tiles = area ÷ tile area × (1 + waste)
Usual waste: 10% straight, 15% diagonal
Worked example
20 m² with 30 × 60 cm tiles and 10% waste:
Tile area: 0.18 m²
Tiles: 20 ÷ 0.18 × 1.10 = 123 tiles
Explanation
Wastage depends on format and cutting
With small tiles laid straight, five per cent usually suffices. With large formats, diagonal or herringbone layouts, or a room with many cuts, you should go to ten or even fifteen. Every cut generates an offcut that rarely gets used elsewhere.
Buy everything from the same batch
Tiles are fired in batches and the shade varies slightly between them. The box shows a batch code and a calibre code. Mixing batches in the same room produces visible differences under raking light, and restocking months later almost never matches.
Keep the leftovers
Hold back half a box once you finish. If a tile breaks years later, finding that model and batch is practically impossible, and replacing one tile with a slightly different one shows more than the crack did.
Grout lines count too
On large surfaces, adding the joint width to the tile width changes the number of pieces needed. With three-millimetre joints and thirty-centimetre tiles the difference is around one per cent, but with small mosaic formats it becomes significant.
Frequently asked questions
How much waste should I allow?
10% for straight laying and 15% for diagonal patterns or lots of cuts. Large formats deserve a bigger margin.
Should I buy everything from one batch?
Yes. Production batches can vary slightly in shade, and a later top-up may be noticeable.
How much wastage should I allow?
Five per cent for straight laying in small formats, and up to ten or fifteen per cent for diagonal, herringbone or rooms with many cuts.
Why buy everything from the same batch?
Because shade varies slightly between firings. Mixing batches produces visible differences, and restocking months later rarely matches the colour.
Need to calculate something else?
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