How to use the tile calculator
Ordering tile is mostly area arithmetic plus a waste factor and a round-up to whole boxes. Get any of those wrong and you either run short mid-job or pay for leftover cartons you cannot return. This calculator keeps the steps in one place.
- Choose feet/inches or metres/cm. Room dimensions use the large unit; tile size uses inches or centimetres.
- Enter room length and width, or paste a known total area if you already have one from a schedule.
- Enter the tile face size and how many tiles ship in one box.
- Set the waste percentage. Start at 10% for a simple layout; raise it for diagonals and complex rooms.
Results show net area, order area with waste, exact tiles needed (rounded up), boxes to buy and the coverage those boxes provide, so you can see the leftover.
Tile quantity formulas
Room area = Length × Width
Tile area = Tile length × Tile width
Net tiles = ⌈Room area ÷ Tile area⌉
Order area = Room area × (1 + Waste % ÷ 100)
Order tiles = ⌈Order area ÷ Tile area⌉
Boxes = ⌈Order tiles ÷ Tiles per box⌉
Always round tiles and boxes up. Partial tiles still consume a full piece, and suppliers sell by the carton. If you are comparing products sold by coverage (for example 1.44 m² per box), set tile size so that tile area × tiles per box equals that coverage.
| Layout | Suggested waste | Why |
|---|---|---|
| Straight stack / grid | 7–10% | Few angled cuts |
| Running bond / brick | 10–12% | More end cuts |
| Diagonal 45° | 12–15% | Triangle waste at edges |
| Herringbone / chevron | 15%+ | Many short cuts and pattern matching |
| Small wet room / niche-heavy | 15–20% | Lots of trims and returns |
Worked examples
A 12 × 10 ft bathroom floor
Area = 120 ft². Tiles are 12 × 24 inches (2 ft² each), 8 per box. Net tiles = 120 ÷ 2 = 60. With 10% waste, order area = 132 ft² → 66 tiles → ⌈66 ÷ 8⌉ = 9 boxes (72 tiles, 144 ft²). That leaves a comfortable spare for breakage.
A metric kitchen splashback
The splashback is 3.6 m long and 0.6 m high: 2.16 m². Tiles are 10 × 20 cm (0.02 m²), 50 per box. Net tiles = 2.16 ÷ 0.02 = 108. With 12% waste for cuts around outlets, order 121 tiles → 3 boxes (150 tiles).
Diagonal hallway in vinyl plank
Hallway 8 × 4 ft = 32 ft². Planks 7 × 48 inches (≈ 2.33 ft²), 12 per box. At 15% diagonal waste, order 36.8 ft² → 16 planks → 2 boxes. Straight-laid would have needed only one box plus a few pieces; the pattern choice meaningfully changes the order.
Who this calculator helps
- Architects and interior designers estimating finishes for budgets and tender packages.
- Tile and flooring contractors preparing material take-offs for quotes.
- Quantity surveyors cross-checking supplier quotes against area schedules.
- Architecture students sizing material quantities in design studio work.
- Homeowners buying tile or vinyl for a renovation without under- or over-ordering.
Ordering tips
- Buy all boxes from the same dye lot; shade variation between batches is common in porcelain and stone.
- Dry-lay a few rows before fixing so you can balance cut widths on opposite walls.
- Keep a labelled spare box for future repairs — matching a discontinued tile years later is rarely possible.
- Confirm the floor area with the square footage calculator, and plan paint for the same rooms with the paint calculator.
Want to see oak, porcelain or polished concrete on the actual floor before you order? Upload a photo and try finishes with AI Flooring.
