Tile Calculator — Free & Easy
Estimate floor or wall tiles, required boxes and purchase cost from a rectangular room layout. Specify separate room and tile units, tile orientation, grout joint, waste and tiles per box.
Loading the interactive calculator. Enable JavaScript to enter your values, or use the formulas and worked example below.
How to use the Tile Calculator
Estimate floor or wall tiles, required boxes and purchase cost from a rectangular room layout. Specify separate room and tile units, tile orientation, grout joint, waste and tiles per box.
- Step 1. Measure the usable rectangular installation dimensions.
- Step 2. Select room units and tile units independently.
- Step 3. Enter tile width/length in the actual installation orientation and the planned grout joint.
- Step 4. Apply your waste percentage and carton quantity; add more for diagonals, cuts and obstacles.
Important: Straight aligned rectangular tile-grid estimator; it does not replace detailed installation layout planning.
Tile Calculator formula explained
Count across = ceil((room width + joint) ÷ (tile width + joint)); count along uses lengths. Grid tiles = across × along. Purchase tiles = ceil(grid tiles × (1 + waste%)); boxes = ceil(tiles ÷ tiles per box).
All calculator outputs depend on the measurements, units and assumptions you enter. Intermediate calculations use unrounded numeric values; formatted results may be rounded for easier reading. For any consequential purchasing or construction decision, verify supplier specifications and regulations.
Worked example with real numbers
For a 12 × 10 ft room and 12 × 12 in tiles with a ⅛-inch joint, the aligned grid is 12 × 10 = 120 tiles. With 10% extra, buy 132 tiles. At 12 tiles per carton, that is 11 cartons.
The example illustrates the formula independently of the interactive fields. You can change the values above to match your own project and compare results.
Frequently asked questions
How much tile waste should I allow?
A 10% allowance is a starting example, not a universal rule. Diagonal layouts, small cut pieces and complex areas often need more.
Does the calculator support metric sizes?
Yes. You may enter the room in meters and tile dimensions in centimeters, or use imperial inputs.
Why is the number of cartons rounded up?
Retail cartons generally cannot be purchased as fractions of a carton. Enter the supplier’s real tiles-per-carton quantity.
Does it account for fixtures or irregular rooms?
No. It calculates one rectangular grid. Break unusual rooms into sections and estimate additional cutting requirements.