How this tile calculator works
Tile is bought three ways at once — by the piece, by the box, and with the setting materials — and all three hang off the same waste-inclusive area:
tiles = buy area ÷ tile ft² · boxes = buy area ÷ box ft² · thinset = buy area ÷ 80/bag
Worked example: tile for a 10 × 12 floor
120 ft² plus 10% waste is 132 ft² to buy. In 12 × 12 tile that's 132 tiles — 9 boxes at 15 ft² a box (about $405) — set with 2 bags of thinset.
How many tiles per square foot?
| Tile size | Per 100 ft² |
|---|---|
| 3 × 6 subway | 800 |
| 12 × 12 | 100 |
| 12 × 24 | 50 |
| 18 × 18 | 45 |
| 24 × 24 | 25 |
Tile FAQ
How many tiles do I need for a 120 square foot floor?
In 12 × 12 in tile: 132 with 10% waste (120 exact). The same floor takes 66 pieces of 12 × 24, 33 of 24 × 24, or about 1,056 subway tiles — the calculator recomputes for any size and shows boxes by your box coverage.
How much extra tile should I buy for waste?
10% for a straight lay in a simple room; 15% for diagonal, herringbone and rooms with many cuts or niches. Buy it all up front from one dye lot — matching a lot later is the classic tile disaster.
How much thinset per square foot?
Plan on a 50 lb bag per ~80 ft² with a ¼ in square-notch trowel — two bags for the default floor. Larger tile wants larger notches (and more thinset): check the trowel size your tile and substrate call for.
How many square feet are in a box of tile?
Commonly 12–20 ft² depending on tile size — it is printed on the box. Type your box coverage in and the calculator orders whole boxes over the waste-inclusive area.
How much does it cost to tile a floor?
Tile itself runs $1.50–8 per ft² for ceramic and porcelain in 2026 ($405 for the default floor at $3/ft² equivalent), plus thinset, grout and spacers. Installed by a setter, floor tile typically prices at $10–20 per square foot.
Embed this tile calculator on your site
Run the tile calculator on your own site, free. Paste the snippet where you want it; the visible credit link is the only condition.