Tile Calculator
Calculate how many tiles you need for floors, walls, or backsplashes with grout spacing and waste factor.
Choosing the Right Tile Size
Small mosaic tiles (1”–4”) work well in showers and backsplashes. Standard 12”×12” ceramic covers exactly 1 sq ft, making math simple. Large-format tiles (18”×18” and up) visually expand a space and have fewer grout lines—but require a very flat substrate (no more than 1/8” variation per 10 feet for tiles over 15 inches). Subway tile (3”×6”) is the default for classic kitchen and bath installs.
Waste Allowance Guidelines
Standard straight-lay patterns: add 10%. Diagonal (45°) or herringbone patterns: add 15–20% because edge cuts waste more material. Irregular room shapes with many cut-outs (toilets, doors, cabinets) push waste toward 15%. Always buy from the same dye lot—a future reorder may not match in color.
Grout and Adhesive Estimates
Sanded grout for joints wider than 1/8”; unsanded for narrower joints or polished stone. As a rough guide, 1 lb of sanded grout covers about 10 sq ft of 12”×12” tile with 3/16” joints. Mosaic tile with 1/8” joints needs roughly 2–3× as much. For thin-set mortar, a 50 lb bag typically covers 40–50 sq ft at a standard 3/16” notch trowel depth.
Frequently Asked Questions
How much grout do I need?
Roughly 1 lb of sanded grout per 10 sq ft for 12×12 tiles with 1/8" joints. Larger joints or smaller tiles need more.
Should I buy extra tiles?
Always buy 10-15% extra. Some tiles break, patterns require cuts, and having spares for future repairs is essential — dye lots vary.