Tile Quantity Calculator — Tiles & Boxes for Floors & Backsplashes
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Tile Quantity Calculator
Find out how many tiles and boxes you need for a floor or backsplash: enter the area and tile size, add waste for the pattern. Free, no sign-up.
- Step 1 — Measure: measure the floor or the backsplash wall with a tape measure.
- Step 2 — Choose: choose straight or diagonal, and type the size of one tile.
- Step 3 — Check the box: if you know how many tiles are in one box, type that number to see boxes too.
No account, no payment, no technical knowledge needed. If you get stuck, press "Fill in an example" below and change the numbers to yours.
Step 1 — How big is the area?
Not sure where to start? Press the example button, see the answer, then change the numbers to your own area.
How to measure a floor: measure one wall to the opposite wall for the length, then the other two walls for the width. How to measure a backsplash: measure along the counter for the length, then from the counter up to the top of the backsplash for the height. Write feet and inches separately. Example: if the tape shows 10 feet 6 inches, type 10 in Feet and 6 in Inches.
Step 2 — What size is one tile, and how will it be laid?
Enter the size of ONE tile, not the box. Example: a tile that measures 12 inches by 12 inches is entered as 12 and 12. A subway tile of 4 inches by 12 inches is entered as 4 and 12.
Waste pays for tiles cut at the edges. Straight rows need about 10%, diagonal needs about 15% because more tiles are cut at angles. Your tile product guide always wins over these starting figures.
Step 3 — How many tiles are in one box? (optional)
If you leave this blank, you still get the number of tiles. To see boxes, type the number of tiles in one box from the box label. Do not guess — every tile box is different.
Save this project
Projects are saved in this browser only. No account, and nothing is sent to a server.
Your result
Enter an area and a tile size to see your result.
Totals are calculated before rounding. Displayed areas are rounded to 2 decimal places. Tiles and boxes are always rounded up to whole numbers.
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How to measure your area
For a floor, measure length and width wall to wall in feet and inches. For a backsplash, measure the wall length along the counter and the height from the counter to the top of the backsplash. Enter feet and inches in the separate fields: 10 feet 6 inches means 10 in Feet and 6 in Inches. Inches must be 0–11 — if your tape shows 12 inches, that is 1 foot, so add 1 to the feet and put 0 in inches.
How the calculation works
First, feet and inches become decimal feet: decimal feet = feet + (inches ÷ 12). Then net area = length × width in square feet. One tile covers (tile length in inches × tile width in inches) ÷ 144 square feet, because 144 square inches make 1 square foot. Order area = net area × (1 + waste ÷ 100). Tiles needed = order area ÷ tile area, rounded up. If you entered tiles per box, boxes = tiles ÷ tiles per box, also rounded up, because you cannot buy part of a box.
Worked examples
Check the calculator against these numbers by hand before trusting it with your own project. They are all worked out with the same formulas above.
| Project | Net area | Order area | Tiles | Boxes |
|---|---|---|---|---|
| Floor 10 ft × 12 ft, tile 12 in × 12 in, straight 10%, 10 tiles per box | 120.00 sq ft | 132.00 sq ft | 132 tiles | 14 boxes |
| Floor 100 sq ft, tile 6 in × 6 in, straight 10% | 100.00 sq ft | 110.00 sq ft | 440 tiles | — (no box size entered) |
| Backsplash 10 ft × 2 ft, tile 4 in × 12 in, straight 10% | 20.00 sq ft | 22.00 sq ft | 66 tiles | — (no box size entered) |
| Floor 8 ft × 10 ft, tile 12 in × 24 in, diagonal 15%, 8 tiles per box | 80.00 sq ft | 92.00 sq ft | 46 tiles | 6 boxes |
Waste allowance guide
| Layout | Starting waste | When it applies |
|---|---|---|
| Straight (tiles in rows) | 10% | Most floors and backsplashes — the default in this calculator. |
| Diagonal (tiles at an angle to the walls) | 15% | Far more edge cuts, so more tiles are lost to cutting. |
| Custom | 0–50% | Use this when your tile product guide states its own figure. |
What this calculator does not do
It does not calculate grout or adhesive. Those are a separate step, and their amounts come from the coverage figures printed on the grout and adhesive products you buy — never guess them from the tile count. It does not price trim, labour, or delivery, and it does not measure a wall with a large window as one piece: for that, measure the tiled parts as separate rectangles and add the tile counts together. This calculator counts tiles and boxes for one rectangular floor or one rectangular backsplash, and it does that one job only.
Common mistakes
- Entering the box coverage (for example "20 sq ft") where the size of one tile belongs — the calculator needs the tile's own length and width in inches.
- Entering inches as 12 or more: inches must be 0–11. Convert 12 inches to 1 foot first.
- Skipping the waste allowance: even a straight layout loses tiles to edge cuts, so 10% is the starting point, not an optional extra.
- Forgetting that a backsplash is measured by wall length and height, not by floor size.
Frequently asked questions
How many tiles do I need for a floor?
Multiply the room length by the room width to get the area in square feet, add a waste allowance for cuts, then divide by the area of one tile and round up. For example, a 10 ft by 12 ft floor is 120 sq ft; with 10% waste that is 132 sq ft, and with 12 in by 12 in tiles (1 sq ft each) you need 132 tiles.
How do I measure a backsplash?
Measure the length of the wall along the counter and the height from the counter to the top of the backsplash, in feet and inches. Multiply them to get the area. Small cuts around outlets are covered by the waste allowance.
What tile size should I enter?
Enter the size of one tile in inches, exactly as printed on the tile box — for example 12 and 12 for a 12 in by 12 in tile. Do not enter the box coverage here; box coverage is a different number and is not used by this calculator.
How much waste should I add for a diagonal tile pattern?
Start with 15% for a diagonal pattern, because far more tiles are cut at angles at the edges. A straight pattern starts at 10%. If your tile product guide states a different figure, use the Custom option and enter that figure.
Why are tiles rounded up instead of down?
You cannot buy part of a tile, and rounding down would leave you short of the area to cover. Rounding up guarantees you have at least the order area, plus a few spares for future repairs.
What if I do not know how many tiles are in a box?
Leave the tiles-per-box field blank. The calculator will still show the number of tiles you need. To see boxes, check the tile box label for the number of tiles per box and enter that number.
Does this calculator work out grout or adhesive?
No. This calculator counts tiles and boxes only. Grout and adhesive are a separate step: use the coverage figures printed on the grout and adhesive products you buy. Do not guess grout from the tile count.
What if my wall has a large window in the middle?
This calculator measures one rectangle. For a wall with a large window, measure the tiled parts as separate rectangles, run each through the calculator, and add the tile counts together. The waste allowance covers small outlet and switch cuts, not a whole window.
Last updated: 26 October 2026. Waste percentages are starting points; your tile product guide overrides them.