Tile Calculator
Estimate whole tiles and full boxes for floors, walls, backsplashes, and other rectangular surfaces.
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Advanced options
Use the piece count printed on the product box or specification.
How to Use
- Choose how to enter the project - use length and width, or enter a known square-foot or square-metre area.
- Select the tile size - pick a common size or choose Custom and enter the tile dimensions.
- Set one waste allowance - the result already includes the selected percentage, so do not add it a second time.
- Enter tiles per box if known - the advanced option converts the tile quantity into full boxes and shows the spare pieces.
- Order whole quantities - the calculator rounds tiles and boxes up because partial pieces and partial boxes cannot be purchased.
Multiply the project length by its width to find the area, divide by the area of one tile, then add one waste allowance and round up. A 12 × 12 inch tile covers 1 square foot, so a 10 × 10 ft room needs 100 tiles before waste and 110 with a 10% allowance. Enter tiles per box to convert the result into full packages.
Setting the tile yourself?
A tile leveling system can help keep adjacent tile edges aligned while the mortar cures.
Tile leveling kit on AmazonAs an Amazon Associate, CalcShed earns from qualifying purchases.How to Measure a Tile Project
For a floor, measure the usable length and width. For a wall or backsplash, measure the horizontal length and vertical height. Enter the measurements directly, or use the known-area mode when the square footage is already available.
For an L-shaped room or several wall sections, split the project into rectangles, calculate each area, and add the areas together before using known-area mode. Subtract large openings that will not be tiled, such as a door or a wide window. Small penetrations are usually covered by the waste allowance.
Measure the actual tile or sheet that will be installed. Product names can be nominal: a tile sold as 12 × 24 inches may have slightly different manufactured dimensions. For ordering, also verify the manufacturer's stated square-foot coverage per box.
Project Dimensions and Tile Dimensions
How Many Tiles Fit in One Square Foot
How Many Tiles in a Square Foot
Use this table for a quick quantity check before waste. The calculator uses exact stored areas rather than the rounded display values.
| Tile Size | Tiles per sq ft | Coverage per Tile |
|---|---|---|
| 4 × 4 in | 9 | 0.111 ft² |
| 3 × 6 in | 8 | 0.125 ft² |
| 6 × 6 in | 4 | 0.250 ft² |
| 9 × 9 in | 1.78 | 0.563 ft² |
| 12 × 12 in | 1 | 1.000 ft² |
| 12 × 24 in | 0.5 | 2.000 ft² |
| 18 × 18 in | 0.44 | 2.250 ft² |
| 24 × 24 in | 0.25 | 4.000 ft² |
For example, 100 square feet requires 400 pieces of 6 × 6 tile or 25 pieces of 24 × 24 tile before waste. The final order must still be rounded up and, when applicable, rounded again to full boxes.
Waste Allowance by Layout
Waste covers perimeter cuts, breakage, damaged pieces, and future repairs. These percentages are planning starting points rather than universal installation rules.
| Layout or Project | Starting Allowance | Why |
|---|---|---|
| Simple straight grid | 10% | Most cuts occur at walls and fixed obstacles |
| Diagonal layout | 15% | More perimeter pieces are cut at an angle |
| Herringbone or intricate pattern | 15–20% | Frequent angled cuts create more offcuts |
| Irregular room or many corners | 15–20% | More edges, jogs, and small pieces |
| Repair with exact replacement stock | Custom | Use the allowance appropriate to the known repair plan |
The calculator result already includes the selected allowance. Do not add the same percentage again. Box rounding may create additional spare tiles, which can be kept for repairs.
Why Some Layouts Create More Waste
Tile Calculator Formulas
The calculator uses the following quantity and package formulas:
Tile area = Tile Length × Tile Width
Base tiles = Project Area ÷ Tile Area, rounded up
Tiles with waste = Project Area × (1 + Waste %) ÷ Tile Area, rounded up
Full boxes = Tiles to Order ÷ Tiles per Box, rounded up
Spare tiles = (Full Boxes × Tiles per Box) − Tiles to Order
Standard quantity estimates commonly rely on the waste allowance rather than calculating grout joints as a separate area deduction. Confirm the planned joint width and layout against the tile manufacturer's installation instructions.
How to Calculate Boxes and Spare Tiles
Tile boxes vary by product. Some labels state tiles per box, while others state square feet per box. This calculator uses tiles per box, so enter the piece count printed on the package or product specification.
The box result is rounded up to a whole package. If the project needs 88 tiles and a box contains 12, the order is 8 boxes, or 96 purchased tiles. The 8 remaining pieces are not an additional waste percentage; they are the result of full-box purchasing and can be stored for future repairs.
Worked Examples
Bathroom floor with 12 × 12 tile. An 8 × 10 ft floor is 80 ft². With a 10% allowance, the calculator uses 88 ft² and returns 88 tiles. At 12 tiles per box, order 8 boxes, which contain 96 tiles and leave 8 spare.
Kitchen floor with 12 × 24 tile. A 10 × 14 ft floor is 140 ft². Each tile covers 2 ft². With a 10% allowance, the order is 77 tiles. If the layout is diagonal and the selected allowance is 15%, the order becomes 81 tiles.
Tile Size Selection Guide
Tile size affects appearance, handling, cut frequency, and substrate demands. The calculator handles quantity; the product and installation system must still be chosen for the actual surface.
| Tile Size | Typical Uses | Planning Note |
|---|---|---|
| 4 × 4 or 6 × 6 in | Backsplashes, shower details, small surfaces | More pieces and more grout joints |
| 12 × 12 in | Floors and walls | Simple one-square-foot reference size |
| 12 × 24 in | Modern floors and shower walls | Check orientation and edge cuts |
| 18 × 18 or 24 × 24 in | Larger floors and open areas | Flatness and handling become more important |
| Custom or mosaic sheet | Product-specific designs | Enter the actual piece or sheet dimensions |
For products sold by sheet, treat one sheet as the tile unit and enter the sheet dimensions. For products sold only by square-foot coverage per box, verify the supplier's package coverage before ordering.
After the Tile Is Set
Tile quantity is only one part of the installation. The next material estimates usually cover the joints and perimeter.
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