Tile Calculator
How many tiles for a floor or wall
Tiling a floor, wall, backsplash or shower? Enter the area in feet or metres to see how many tiles you need in common sizes, with waste for cuts and breakage. Below you'll find a tiles-per-square-metre chart, how much waste each layout really needs, a worked bathroom example, and how much thinset and grout to order alongside.
How many tiles do I need?
Two steps. First find your area: length × width, in whichever unit your supplier quotes. Then divide by the coverage of one tile, and add waste for cuts and breakage.
Work in the unit you'll buy in. UK, Irish and European suppliers price tile by the square metre; US suppliers price by the square foot or by the box. Use the Imperial/Metric toggle above so you never have to convert by hand.
Rule of thumb: a 30×30 cm tile is about 11 per m². A 12×12 in tile is exactly 1 per ft². Everything else scales from there.
Tiles per square metre and square foot
How many 60x60 tiles per m2 is the question we get most, and the answer is 2.8. Use this as a tile coverage calculator in either unit: tiles per square foot for US suppliers, tiles per m2 for UK, Irish and European ones. Coverage is shown before waste, for the sizes most suppliers stock. Metric and imperial sizes are near-equivalents, not exact matches (30 cm is 11.8 in), so check the actual size on the box.
| Tile size | Nominal imperial | Tiles per m² | Tiles per ft² |
|---|---|---|---|
| 10 × 10 cm | 4 × 4 in | 100 | 9 |
| 15 × 15 cm | 6 × 6 in | 44.4 | 4 |
| 20 × 20 cm | 8 × 8 in | 25 | 2.25 |
| 30 × 30 cm | 12 × 12 in | 11.1 | 1 |
| 30 × 60 cm | 12 × 24 in | 5.6 | 0.5 |
| 45 × 45 cm | 18 × 18 in | 4.9 | 0.44 |
| 60 × 60 cm | 24 × 24 in | 2.8 | 0.25 |
| 20 × 120 cm plank | 8 × 48 in | 4.2 | 0.38 |
The printable material coverage chart lists tiles per square foot for every common size in one place, along with grout and thinset coverage, so you can check a box count at the merchant without reloading this page.
How much waste to add for tile
Waste is not padding, it is the tile that ends up in the offcut pile. A diagonal layout cuts every perimeter tile at 45°, and almost none of those offcuts are reusable, which is why the percentage climbs.
| Layout or situation | Add | Why |
|---|---|---|
| Straight grid, square room | 10% | Perimeter cuts only |
| Brick or offset bond | 10% | Half tiles at alternate rows |
| Diagonal (45°) | 15% | Every edge tile is cut twice |
| Herringbone or chevron | 15 to 20% | Angled cuts, few reusable offcuts |
| Large format (60 cm and up) | 15% | Breakage, and one bad cut wastes a lot |
| Irregular room | 15% | More edges means more cuts |
Buy the whole job in one batch. Tile is fired in lots and shade varies noticeably between them, so a top-up order weeks later can arrive visibly different. Keep a few spares from that batch for future repairs.
Worked example: tiling a 3 × 4 m bathroom floor
The floor is 12 m² (about 129 ft²), tiled in 60 × 60 cm porcelain, straight grid.
| Step | Working | Result |
|---|---|---|
| Floor area | 3 m × 4 m | 12 m² |
| Add 10% waste | 12 × 1.10 | 13.2 m² |
| Tiles needed | 13.2 ÷ 0.36 m² | 37 tiles |
| Boxes (4 tiles = 1.44 m²) | 13.2 ÷ 1.44 | 10 boxes |
Order by the box, not the tile: suppliers rarely split them, so you round up to the next full box anyway. Check the box coverage on the label, since it varies by tile thickness and range.
Floor tile vs. wall tile
Floor tiles are rated for foot traffic (look for a PEI rating of 3 or higher) and for slip resistance; wall tiles are thinner and lighter. Don't put wall tile on a floor. For showers and wet areas, choose porcelain or glazed ceramic with a low water-absorption rating.
Thinset, grout and adhesive quantities
Adhesive coverage depends on the trowel notch, which in turn depends on tile size. Bigger tiles need a deeper notch, so a bag goes far less far than people expect.
| Trowel notch | Suits tile up to | Coverage per bag |
|---|---|---|
| 3/16 in V-notch | Mosaic and small wall tile | ~95 ft² (8.8 m²) |
| 1/4 × 1/4 in square | 20 to 30 cm (8 to 12 in) | ~85 ft² (7.9 m²) |
| 1/4 × 3/8 in | 30 to 45 cm (12 to 18 in) | ~60 ft² (5.6 m²) |
| 1/2 × 1/2 in | 60 cm (24 in) and larger | ~40 ft² (3.7 m²) |
Grout use rises with narrow joints and small tiles, because there is more joint length per square metre. Manufacturers' coverage figures vary a lot by joint width and depth, so work from the figure on your specific bag rather than a generic rule. Large-format tiles should also be back-buttered for full contact.
What tiling a room costs
Tile itself commonly runs $1 to $15 per ft² (roughly £10 to £120 per m²): basic ceramic at the bottom, porcelain in the middle, natural stone at the top. Professional installation typically adds $5 to $15 per ft² depending on layout complexity and whether the substrate needs work.
Don't forget the extras that catch people out: adhesive, grout, spacers, silicone, trim or edging strips, backer board for wet areas, and hire of a wet saw. On a small bathroom these can add as much as the tile.
Tile mistakes that cost you a second order
- Ordering the exact area. Every job has cuts. 10% is the minimum, not the maximum.
- Splitting the order across batches. Shade varies by production lot and it shows under a bathroom light.
- Using the room's floor area for a wall job. Measure each wall, then subtract the door and window openings.
- Forgetting the layout multiplier. Herringbone can need twice the waste of a straight grid.
- Buying wall tile for a floor. Check the PEI rating before you order, not after.
- Keeping no spares. One cracked tile in three years means re-tiling the room if the batch is gone.
How this tile calculator works out its numbers
Tile counts are area ÷ the face area of one tile, plus waste. Metric and imperial are calculated separately rather than converted, because the sizes are not equivalent: a 60 cm tile is 0.36 m² while a 24 in tile is 0.3716 m², about 4% larger. Treating them as the same understates metric counts.
- Waste defaults to 10% for a straight grid, rising to 15% for diagonal and large-format layouts and up to 20% for herringbone, reflecting how much of each cut is reusable.
- Thinset coverage figures are the trowel-notch ranges published on manufacturer bags, which vary by brand.
Figures reviewed . Every worked example on this page is checked against the calculator above.
Tile Calculator: frequently asked questions
How many tiles per square metre?
About 11 for a 30×30 cm tile, 25 for a 20×20 cm tile, 4.9 for a 45×45 cm tile, and roughly 2.8 for a 60×60 cm tile, all before adding waste. Switch the units toggle to metres to enter your room directly in m².
How many 60x60 tiles do I need per m²?
About 2.8, since one 60×60 cm tile covers 0.36 m². For a 12 m² floor that is roughly 34 tiles bare, or 37 once you add 10% waste. Suppliers usually sell them 4 to a box, covering 1.44 m².
How much extra tile should I buy?
10% for a straight grid in a square room, 15% for diagonal, large-format or irregular rooms, and 15 to 20% for herringbone or chevron. Buy it all in one batch, as shade varies between production lots.
How do I figure tiles for an odd-shaped room?
Break the space into rectangles, calculate each, and add them together using the 'number of areas' field. For walls, measure each wall separately and subtract door and window openings.
How much thinset do I need?
It depends on trowel notch, not just area. A 50 lb bag covers roughly 85 ft² with a 1/4 inch square notch, but only about 40 ft² with the 1/2 inch notch that large-format tile needs. Back-butter big tiles for full coverage.
Should I work in square feet or square metres?
Work in whichever unit your supplier prices in. UK, Irish and European sellers quote per square metre; US sellers quote per square foot or per box. The Imperial/Metric toggle on this calculator converts either way so you can order without doing the maths.
How much does it cost to tile a room?
Tile commonly runs $1 to $15 per ft² depending on material, with professional installation adding roughly $5 to $15 per ft². Budget separately for adhesive, grout, trim, backer board and saw hire, which add up fast on small bathrooms.