Tile calculator
Room size, tile size, and joint width to a tile count you can order — with the waste factor matched to how you're laying it.
Each tile’s footprint includes the grout joint on two sides — the standard estimating convention. Buy whole boxes and keep spares from the same dye lot for future repairs.
Choosing the waste factor
Waste isn’t pessimism, it’s geometry: every wall the tile meets produces cut pieces, and only some offcuts are reusable at the next row. For a straight lay in a rectangular room, ~10% extra is the trade convention. Go to 15–20% for diagonal lays — at 45° every perimeter cut is a triangle and its mirror is rarely usable — and for rooms with alcoves, plumbing, or many corners. Herringbone and other patterns sit at the high end too.
Large-format tile changes the arithmetic: one broken 12×24 costs you 2 ft² of coverage, so the same percentage buys you fewer spare pieces. When the count is small, round up generously.