Work out how many tiles you need for a floor or wall from your room size and tile size, including a waste allowance and an estimated material cost.
Results
Calculated
Tiles to buy
—
Rounded up, waste included
Room area
—
Square feet to cover
Exact tiles needed
—
Before rounding up
Estimated cost
—
Tiles to buy × price each
Add this calculator to your website
How to use this calculator
Enter the dimensions of the room (or wall) you're tiling, the dimensions of a single tile, and a waste allowance for cuts and breakage, then click Calculate. The calculator divides the total area by the area of one tile, adds the waste percentage, and rounds up to the nearest whole tile since partial tiles still require a full tile to cut from. Click Clear to reset all fields.
Understanding the inputs
Room length and width are entered in feet, and tile length and width are entered in inches — the calculator converts units automatically so you don't have to. The waste allowance covers cutting losses around edges and fixtures, breakage, and spares for future repairs; 10% is standard for a straight (grid) layout, while diagonal, herringbone, or heavily-cut layouts typically need 15% or more. Price per tile is optional and only used to estimate total material cost.
Interpreting the results
Tiles to buy is the number to purchase, rounded up after waste is added. Room area is the raw square footage being covered. Exact tiles needed shows the unrounded figure so you can see how much the waste allowance and rounding added. Estimated cost multiplies tiles to buy by the price per tile you entered.
Frequently Asked Questions
How many tiles do I need for a room?
Divide the room area by the area of a single tile, then add a waste allowance. Room area is length times width, and tile area is the tile's length times width (converted to the same units). For example, a 12 x 10 ft room (120 sq ft) using 12 x 12 in tiles (1 sq ft each) needs 120 tiles before waste, or 132 tiles with 10% waste.
How much extra tile should I buy for waste?
A common rule of thumb is 10% extra for a straight layout, and 15% or more for diagonal patterns, herringbone layouts, or rooms with many cuts around corners, fixtures, or doorways. The waste allowance covers cutting losses, breakage, and future repairs.
How do I calculate tile square footage?
Multiply a tile's length by its width to get its area, then multiply by the number of tiles to get total coverage. Keep units consistent — if the tile is measured in inches, divide by 144 to convert square inches to square feet before comparing it to a room measured in square feet.
Should I round the number of tiles up or down?
Always round up to the next whole tile. Partial tiles still require a full tile to cut from, so rounding down would leave you short. This calculator rounds the final tile count up automatically after applying the waste percentage.