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Make It Fit

Flooring & Tile

Tile Calculator

Work out how many tiles — and how many boxes — a floor or wall needs, with a sensible allowance for cuts.

Calculate your tiles

Areas in feet, tile size in inches. Split an irregular room into more than one area, or exclude anything you won't tile. The estimate updates as you type.

Area to tile

Area 1

ft
ft
Tile
in
in
tiles
Waste
%

The method

  1. 01

    Area to tile

    length (ft) × width (ft)

    This gives the area of one rectangle. For an L-shaped or irregular room, split it into more than one rectangle and add them — the calculator above does this with "Add another area". Anything within that space you won't tile, like a shower tray or an island, comes off the total with "Exclude an area".

  2. 02

    Area of one tile

    tile width (in) × tile height (in)

    Use the nominal tile size printed on the box; the grout joint is small enough to ignore at this stage.

  3. 03

    Tiles before waste

    area to tile ÷ area of one tile

  4. 04

    Add a waste allowance

    tiles × (1 + waste allowance)

    Around 10% for a straight layout in a simple rectangular room; 15% or more for diagonal or patterned layouts. The calculator above applies this for you.

  5. 05

    Boxes to buy

    round up (tiles with waste allowance ÷ tiles per box)

    Rounds up to the next whole box, since boxes can't be split.

Worth knowing

  • Buy all boxes from the same batch where you can — shade varies between production runs.
  • Keep a few spare tiles after the job for future repairs.
  • Irregular rooms are easier to measure as several rectangles added together — use "Add another area" for each one.

Tile calculator example

Room
10 × 12 ft
Tile
12 × 12 in
Tiles per box
10
Waste allowance
10%
  1. Room area10 × 12 = 120 sq ft
  2. One 12 × 12 in tile1 sq ft
  3. Tiles before waste120 tiles
  4. After 10% waste120 × 1.10 = 132 tiles
  5. Boxes132 ÷ 10 = 13.2 boxes
  6. Round up14 boxes

Buy 14 boxes.

14 boxes contain 140 tiles, giving 140 sq ft of purchased coverage.

How much extra tile should you buy?

A waste allowance covers cuts around edges and obstacles, breakage, the odd damaged tile, pattern or layout requirements, and a few spares kept back for future repairs.

LayoutTypical waste allowance
Straightforward layoutAbout 10%
Diagonal or more cut-heavy layoutAbout 15%
Complex patterns / many cuts15% or more may be appropriate

Important: these are practical starting points, not guarantees. Unusual tile shapes, mosaics, herringbone layouts, a very small room with many cuts, or the manufacturer's own recommendation may justify a different allowance.

How much extra tile should you buy? goes further into what the allowance covers, and why whole boxes, dye lots and return policies affect the number you order.

How to measure an irregular room for tile

A quick example of adding rectangles together:

Area 1: 10 × 8 ft
80 sq ft
Area 2: 4 × 3 ft
12 sq ft
Gross area
92 sq ft

Tile calculator FAQ

How do I calculate how many tiles I need?
Work out the area in square feet, divide by the area of one tile, add a waste allowance, then divide by tiles per box and round up to a whole box. The calculator above does all of this for you as you type.
How much extra tile should I buy for waste?
About 10% is a reasonable starting point for a straightforward, single-direction layout. Diagonal, patterned, or cut-heavy layouts often need 15% or more — see the guidance above for details.
Should I subtract cabinets, islands, or other areas?
Yes, if part of the room won't be tiled. Use "Exclude an area" for each rectangular section — a kitchen island or a fixed cabinet base, for example — and the calculator subtracts it from the total before working out tiles and boxes.
Do grout joints change the tile calculation?
This calculator uses nominal tile dimensions and doesn't attempt a grout-joint layout calculation. For ordinary material estimating, that's a practical approximation. Detailed layout planning — working out exact cut positions, for instance — may need to account for joint width and room geometry as well.
Should I round up when buying boxes of tile?
Yes — the recommendation above rounds up to the next whole box, since tile is generally sold by the box rather than individually. Check the box contents and your retailer's return policy against what you actually need before you buy.

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