Tile Calculator

Tile is bought by the box, so the job is really two steps: work out the area to cover, then turn that into whole tiles and boxes for the size you have chosen. Enter a room size or a total area, add your tile dimensions and a waste allowance, and get the tiles needed, the boxes to order and the estimated cost — for a floor or a wall.

%
$
Tiles needed — incl. waste
Boxes — to order
Floor area — sq ft
Tile size — sq ft each
Estimated cost — at price per box

How to Calculate Tiles

Give it an area, a tile size, and read the boxes.

1

Choose how to enter the size

Use Room to type a length and width in feet or metres and let the calculator work out the area, or Area if you already know the total square footage of the floor or wall.

2

Enter the tile and box

Type the tile width and height in inches and how many tiles come in a box — both are printed on the product label. Set a waste allowance to cover cuts and breakages.

3

Read tiles, boxes and cost

You get the tiles needed with waste, the whole boxes to order, the coverage of one tile, and — with a price per box — the estimated cost. Round up when you buy.

Frequently Asked Questions

How many tiles do I need per square foot?
It depends on the tile size, because a bigger tile covers more area so you need fewer of them. Work out the area of one tile in square feet by multiplying its width by its height in inches and dividing by 144, then divide your floor or wall area by that figure. A 12 by 12 inch tile is exactly one square foot, so you need roughly one tile per square foot; a 6 by 6 inch tile covers a quarter of that, so you need about four per square foot; a large 24 by 24 inch tile covers four square feet, so one tile does the work of four. The calculator does this for you: enter the tile width and height in inches and it works out the coverage per tile and the number of tiles for your area, then adds a waste allowance on top.
How much extra tile should I buy for waste?
A waste allowance of about ten percent is the usual starting point for a straight grid layout, and it covers the tiles lost to cuts at the walls, the odd breakage, and a few spares kept back for future repairs. Bump it up when the job is more demanding: allow around fifteen percent for a diagonal layout or a running-bond pattern, and closer to twenty percent for herringbone, a very busy room with lots of corners and cabinets, or when you are working with large-format tiles where a single bad cut wastes a lot of material. The calculator adds your chosen waste percentage on top of the bare tile count and shows both numbers, so you can see the raw figure and the amount to actually order.
How many boxes of tile do I need?
Tile is sold by the box, and each box holds a set number of tiles that covers a fixed area, so once you know how many tiles you need you divide by the tiles per box and round up to whole boxes. The tiles per box is printed on the label and varies with tile size, so smaller tiles pack more to a box and large-format tiles far fewer. Enter the tiles per box for your product and the calculator divides your tile count, waste included, by that number and rounds up, because you cannot buy part of a box. Buying whole boxes is also why a little overage is unavoidable, and it is worth keeping the leftovers from the same batch so any future replacement matches the colour and shade exactly.
How much area does a 12x12 tile cover?
A 12 by 12 inch tile covers exactly one square foot, because twelve inches is one foot and one foot by one foot is a square foot. That makes 12 by 12 tiles the easy case: the number of tiles before waste is almost the same as the floor area in square feet, so a 120 square foot room needs about 120 tiles plus a waste margin. Metric 300 by 300 millimetre tiles are marketed as the same size but are very slightly smaller at about 0.97 square feet each, so you need a touch more of them for the same area. The calculator uses the exact tile dimensions you enter rather than the nominal name, so the coverage per tile and the tile count stay accurate whichever size you choose.
How do I measure an L-shaped room for tile?
Split the L-shaped room into two simple rectangles, work out the area of each by multiplying its length by its width, then add the two areas together to get the total to tile. Draw the room, extend one wall across on your sketch to divide it into a larger rectangle and a smaller one, and measure the length and width of each part. Add the two square-foot figures and enter the sum in the calculator's Area mode, or run the two rectangles separately in Room mode and add the tile counts. Either way, keep the waste allowance in mind because an irregular room has more edges and cuts than a plain rectangle, so lean toward the higher end of the waste range.

More home & DIY calculators