Tile calculator
Room size and tile size, plus an allowance for cuts and breakages.
- Runs in your browser — nothing you enter is uploaded
- No sign-up, no quotas, free to use as often as you like
How it works
Tiles are bought in boxes and dye lots, so ordering short is genuinely awkward — a later box can be visibly a different shade. The allowance for waste is not padding; it is the part of the order that makes the job finishable.
Why you need a waste allowance
Tiles at the edges get cut, and the offcuts are usually unusable. Ten per cent covers a simple rectangular room laid straight. Go to fifteen for a room with alcoves or many corners, and twenty for a diagonal or herringbone layout, which generates far more cutting.
Buy from one batch
Tiles are produced in batches and the colour varies slightly between them. Buying everything at once, from the same batch, avoids a patch that does not quite match. Keeping a few spares afterwards is worth the space — replacing a cracked tile years later from a different batch rarely looks right.
Walls as well as floors
The calculation is the same for a wall: enter the wall's width and height instead of the room's dimensions.
Tiles per square metre
That figure is shown too, because it is what tile shops quote and it makes comparing products straightforward.
Tile calculator — questions
How much waste should I allow?
Ten per cent for a simple rectangular room, fifteen for an awkward one, twenty for diagonal or herringbone patterns.
Does it account for grout lines?
Not explicitly. Grout lines slightly reduce the number needed, which the waste allowance more than covers.
Can I use it for walls?
Yes. Enter the wall's width and height in place of the room dimensions.
Why buy from one batch?
Colour varies slightly between production batches, so a top-up order can be visibly different.
What if my tiles are not rectangular?
Enter the dimensions of the smallest rectangle the tile fits inside, then add extra waste.