How this tile calculator works
MaterialRaft first adds each room’s length × width, then subtracts any entered area you do not intend to tile. It multiplies your net total by an adjustable allowance for offcuts, breakage, and fitting around edges. Dividing that adjusted coverage by the area of one tile gives an estimated number of individual tiles. The final box count always rounds upward, because stores normally sell tile by the full box.
For example, a 12 × 10 foot room has 120 square feet of floor. If you choose 12 × 24 inch tiles, each nominal tile covers 2 square feet. A 10% planning allowance gives 132 square feet, or 66 whole tiles. With 8 tiles per box, you need 9 complete boxes (72 tiles purchased).
Real installations vary. A pattern with difficult cuts, multiple irregular corners, a small repair later, or tiles sold by stated box coverage may change your purchasing decision. Check the manufacturer's specifications and ask an experienced installer if the layout is complex.
Frequently asked questions
Do I need to add extra tiles?
Usually it is sensible to budget for cutting and damage. The appropriate amount depends on the job, not a fixed universal percentage.
Does the calculation include grout joints?
No. It uses nominal tile dimensions and a planning allowance. Joint layout requires a more detailed installation plan.
Can I calculate an L-shaped room?
Yes. Divide it into non-overlapping rectangular sections, then add each as a room or zone.
Will this estimate my total installation bill?
No. The optional cost uses price × boxes only; it excludes labor and other supplies.
Explore our step-by-step guide to tile box quantities and tile waste planning guide.