Tile Calculator
Calculate the number of tiles needed for a room or wall with a wastage factor for cuts and breakage.
How to use the Tile Calculator
- Enter your inputs into the Tile Calculator above.
- Results update instantly as you type — no submit button needed.
- Adjust any value to see how the result changes in real time.
The tile quantity formula
Tiles needed = ⌈(Area to cover × (1 + waste %)) / Area per tile⌉
Calculate area to cover, multiply by 1 + waste percentage, divide by area of one tile. Round up. Add box quantity rounding (tiles often sold by box, so order one box more than strict need).
Worked example
120 sq ft floor, 12"×12" tiles (1 sq ft each), 10% waste: 120 × 1.10 = 132 tiles. Sold in boxes of 12: round up to 144 tiles (12 boxes). Keep extras for future repairs.
Frequently asked questions
How much waste should I plan for?
Simple rectangular floor: 10%. Diagonal pattern: 15%. Herringbone or complex patterns: 20%. Multiple rooms with cuts at doorways: 15%.
Do I need to buy extras for repairs?
Yes — at least 5 spare tiles after installation. Tile production runs vary slightly in color; matching tiles years later can be impossible.
What's a tile lippage?
Height difference between adjacent tiles. Should be minimal (<1/32"). Caused by uneven substrate or warped tiles. Tile leveling systems help.