Tile Calculator
Calculate how many tiles you need for a room, including extra for cuts and breakage — free and instant.
Advanced options
Your result
Updates as you type- Tiles needed
- 37
- Room area
- 12 m²
- Tile area
- 0.36 m²
Rounded up, with your wastage allowance included.
Area after subtracting untiled exclusions.
Coverage of a single tile.
Method, assumptions, and tips
Grout uses tile pitch: (length + gap) × (width + gap). Purchased coverage uses physical tile area; the estimate is not a cut plan. Excluded area cannot exceed gross area.
Assumes a simple rectangular room with no allowance for offsets or patterns.
Rounds up to the nearest whole tile.
Metric and US units are converted with the exact international factors.
Optional grout gap adjusts tile pitch; a zero gap keeps the conservative area-only estimate.
Box count and cost are optional and only shown once you enter tiles-per-box and a price.
We divide your room area by a single tile's area to find how many tiles fit, then add your wastage percentage to cover cuts, breakage, and future repairs.
Buy your tiles in one batch — dye lots differ between production runs, and a later top-up rarely matches.
Estimating a straightforward rectangular floor or wall before a trip to the tile shop.
How it works
Working out how many tiles you need
The question "how many tiles do I need" comes down to dividing one area by another, then buying more than the answer. This calculator does both steps:
- Room area = length × width
- Tile area = tile length × tile width
- Tiles needed = (room area ÷ tile area) × (1 + wastage), rounded up
The rounding up matters. You cannot buy 36.4 tiles, and the fraction you round away is precisely the cut piece you still have to make.
Tiles per unit area, by size
If you want a quick sanity check on the result, this is how many of each common tile size fits into a given area before wastage:
| Tile size | Per square metre | Per 100 sq ft |
|---|---|---|
| 30 x 30 cm | 11.11 | 104 |
| 45 x 45 cm | 4.94 | 46 |
| 60 x 60 cm | 2.78 | 26 |
| 12 x 12 in | 10.76 | 100 |
| 18 x 18 in | 4.78 | 45 |
| 24 x 24 in | 2.69 | 25 |
Multiply your room area by the relevant figure, add wastage, and you should land within a tile or two of the calculator.
How much wastage to add
Wastage covers three things: tiles cut to fit edges, tiles broken during handling, and spares kept for future repairs. The right allowance depends mostly on the layout.
| Situation | Suggested allowance |
|---|---|
| Simple grid, square room | 10% |
| Brick or offset bond | 10–15% |
| Small room with many cuts | 15% |
| Diagonal or herringbone layout | 15–20% |
| First DIY tiling job | Add 5% to any of the above |
Diagonal layouts need more because almost every perimeter tile becomes a cut, and each cut wastes most of a tile.
Always buy in one batch
This is the mistake that costs the most. Tiles are produced in batches, and colour varies slightly between them — the batch number is printed on the box. If you run out and buy more later, the replacements may not match, and on a floor that difference is visible. Order the full quantity including wastage in a single purchase, and keep the leftovers.
Boxes and cost
Enter tiles-per-box (printed on the box) and a price per box, and the calculator adds a boxes-to-buy figure and an estimated cost, rounded up to whole boxes since that is what you actually purchase. Leave either blank and those two lines simply do not appear — this is optional, not a required step.
What this calculator does not account for
- Exact grout layout. Advanced options can include a grout gap using an area-per-tile approximation. This does not place individual tiles, model perimeter joints or create a cutting plan.
- Unmeasured obstacles. Advanced options subtract the untiled area you enter. The tool cannot identify islands, hearths or built-in furniture from room dimensions; measure those exclusions yourself.
- Complex rooms. For an L-shape or an alcove, split the space into rectangles, run each separately, and add the results.
- Installation cost. The estimated cost above is tiles only — adhesive, grout bags, spacers, and labor are all separate.
Measure twice, add the wastage, and buy it all at once. Everything here is computed in your browser; nothing you enter is sent anywhere.
FAQ
Can I use direct area and box coverage?
Yes. Choose direct area instead of room dimensions. Advanced options subtract untiled areas, add a grout gap and accept coverage per box. Whole boxes are rounded up and extra tiles shown. The grout adjustment is an area approximation, not a layout or cut plan.
How many tiles do I need for my room?
Divide your room area by the area of one tile, then add a wastage allowance and round up. This calculator does all three steps — enter the room dimensions, the tile size and your wastage percentage, and it returns whole tiles.
How much wastage should I add?
Around 10% for a simple grid layout in a square room. Go to 15% for small rooms with many cuts or an offset bond, and 15–20% for diagonal or herringbone patterns. Add another 5% if it is your first tiling job.
Does this account for grout lines?
Yes, optionally. Enter the grout gap in Advanced options. It uses tile pitch as an area approximation. Leave it at zero for an area-only estimate, and keep a waste allowance for cuts.
Can I get a cost estimate, not just a tile count?
Yes, optionally. Enter how many tiles come in a box and the price per box, and the calculator adds a boxes-to-buy figure (rounded up, since you buy whole boxes) and an estimated total cost. Leave either blank to skip this — it covers tiles only, not adhesive, grout, or labor.
Can I use feet and inches?
Yes. Switch the units control to US and enter the room in feet and the tile size in inches. Conversion uses exact factors, so both unit systems agree.
How do I handle an L-shaped room?
Split it into rectangles, run the calculator once for each, and add the results. Do the same for alcoves. Subtract permanent obstacles like a kitchen island by measuring only the area you are actually covering.
Why should I buy all the tiles at once?
Colour varies slightly between production batches, and the batch number is printed on the box. If you run out and reorder later, the new tiles may not match the old ones — a difference that is clearly visible across a finished floor.